CN113305732B - Multi-station full-automatic thinning grinding method for semiconductor equipment - Google Patents

Abstract

The application relates to a multi-station full-automatic thinning grinding method for semiconductor equipment, which comprises the following steps of 1: the workbench drives the wafer bearing table to rotate around a rotating shaft of the workbench, the grinding unit drives the grinding part to rotate around the rotating shaft of the grinding part, and the distance between the grinding part and the opposite surface of the wafer bearing table at the grinding position is adjusted to be the thickness of a finished grinding part; and a step 2: putting the to-be-ground sheet into a sheet loading position; step 3: the workbench drives the wafer bearing table of the wafer loading position to rotate to the grinding position; and step 4: the grinding piece grinds the to-be-ground sheet rotating around the rotating shaft of the workbench; step 5: the workbench drives the wafer bearing table of the grinding position to rotate to the wafer unloading position; step 6: and taking the grinding finished product off the chip unloading position. This application has the effect that improves the attenuate grinding efficiency of wafer.

Description

Multi-station full-automatic thinning grinding method for semiconductor equipment

Technical Field

The application relates to the field of semiconductor processing production, in particular to a multi-station full-automatic thinning and grinding method for semiconductor equipment.

Background

The semiconductor equipment for wafer thinning is mainly applied to wafer thinning and grinding in the fields of integrated circuits, discrete devices, LEDs, GPP chips and the like. The prior grinding process method of the semiconductor equipment for thinning is a deep-feed grinding method, namely a deep-cut slow-feed grinding method.

According to the grinding method, after the grinding wheel rotates at a high speed and is fed downwards to the height position of the initial thickness of the wafer, the wafer rotates below the grinding wheel along with the rotation of the workbench, the main shaft drives the grinding wheel to feed downwards slowly, the grinding wheel is in contact with the surface of the wafer to remove the trace thickness of the wafer, the workbench continuously drives the wafer to rotate below the grinding wheel for multiple times, the grinding wheel removes the trace thickness of the wafer for multiple times, the grinding is completed after all wafers on the workbench are machined to the set target thickness, the main shaft drives the grinding wheel to ascend to the initial position, and the workbench stops rotating.

Disclosure of Invention

In order to improve the thinning and grinding efficiency of the wafer, the application provides a multi-station full-automatic thinning and grinding method for semiconductor equipment.

The application provides a multistation full-automatic thinning grinding method for semiconductor equipment, adopts following technical scheme:

in a first aspect, the present application provides a multi-station thinning grinding method for semiconductor equipment, which adopts the following technical scheme:

a multi-station thinning grinding method for semiconductor equipment comprises a grinding unit, a workbench, wherein a plurality of wafer bearing tables are arranged on the workbench, and the wafer bearing tables drive a wafer to be ground to move to an area in contact with a grinding part to be a grinding position; the wafer bearing table moves to a region for placing the wafer to be ground on the wafer bearing table to be a wafer loading position; the wafer bearing table moves to a region where the wafer to be ground is unloaded from the wafer bearing table to be a wafer unloading position; the grinding piece to be ground after grinding is a grinding finished product; the method is characterized in that: the workbench drives the wafer bearing table to rotate circumferentially, and the workbench drives the wafer bearing table to move from a wafer loading position to a grinding position and from the grinding position to a wafer unloading position in sequence; in the process that the to-be-ground sheet on the sheet bearing table moves from the sheet loading position to the grinding position and from the grinding position to the sheet unloading position, the to-be-ground sheet is tightly connected with the sheet bearing table;

the grinding unit is provided with a grinding part for grinding the part and can drive the grinding part to rotate; the distance between the grinding part and the wafer bearing table can be adjusted and kept stable after movement; after the distance between the grinding piece and the wafer bearing tables is adjusted once, the to-be-ground wafers on the two wafer bearing tables can be ground at least;

when the grinding unit grinds the to-be-ground sheet on the sheet bearing table, the workbench continuously drives the sheet bearing table to move;

step 1: the workbench drives the wafer bearing table to rotate around a rotating shaft of the workbench, the grinding unit drives the grinding part to rotate around the rotating shaft of the grinding part, and the distance between the grinding part and the opposite surface of the wafer bearing table at the grinding position is adjusted to be the thickness of a finished grinding part;

and a step 2: putting the to-be-ground sheet into a sheet loading position;

step 3: the workbench drives the wafer bearing table of the wafer loading position to rotate to the grinding position;

and step 4: the grinding piece grinds the to-be-ground sheet rotating around the rotating shaft of the workbench;

step 5: the workbench drives the wafer bearing table of the grinding position to rotate to the wafer unloading position;

step 6: and taking the grinding finished product off the chip unloading position.

Through adopting above-mentioned technical scheme, to the attenuate grinding of wafer, once grinding targets in place, need not relapse trace grinding many times, the position of grinding piece is when accomplishing a wafer and grinding simultaneously, do not need adjustment height many times, and when prior art accomplished a wafer grinding, the position of grinding piece need descend about 10 times, this scheme has eliminated the error that descending motion part produced at every turn, the grinding precision is higher, simultaneously when grinding piece carries out the attenuate grinding to a plurality of wafers, the grinding piece position remains unchanged, and prior art if will accomplish the grinding to 100 wafers, can divide into 25 groups with the wafer, four wafers of every group, the grinding piece needs the accurate grinding distance that moves 25 times, and the attenuate grinding of 100 wafers just can be accomplished to the accurate distance of this scheme, reduce the error that grinding piece reciprocating motion caused many times.

Preferably, a vacuum assembly is arranged on the wafer bearing table and comprises a control unit for controlling the opening or closing of the vacuum channel and the compressed air channel;

a connecting step 1: in the process that the to-be-ground sheet on the sheet bearing table moves from the sheet loading position to the grinding position and from the grinding position to the sheet unloading position, the vacuum assembly exerts an adsorption effect on the to-be-ground sheet and tightly presses and connects the to-be-ground sheet with the sheet bearing table;

a connecting step 2: when the bearing platform moves to the unloading position, the vacuum assembly exerts the floating sheet effect on the finished grinding part, and the vacuum assembly exerts the acting force separated from the bearing platform on the finished grinding part.

By adopting the technical scheme, when the to-be-ground sheet is placed on the bearing table, the control of vacuum and compressed air is realized through the control unit, so that the functions of sucking and floating the sheet are realized;

opening a control unit of the vacuum assembly to open a vacuum channel, closing a compressed air channel, enabling the vacuum assembly to generate an adsorption effect, keeping the pressing connection between the to-be-ground sheet and the bearing table, and keeping the relative position between the to-be-ground sheet and the bearing table unchanged when the grinding piece grinds the to-be-ground sheet;

when the grinding finished product piece needs to be taken down from the bearing table, the floating piece of the vacuum assembly is started, the control unit controls the vacuum channel to be closed, the compressed air channel is opened, a gap is formed between the grinding finished product piece and the bearing table, and the grinding finished product piece is convenient to take down from the bearing table.

Preferably, the grinding unit further comprises a grinding spindle, a grinding motor and a feeding mechanism; the grinding spindle is fixedly connected with the grinding part, the grinding motor drives the grinding spindle to rotate, the feeding mechanism drives the grinding spindle to move, and the distance between the grinding part and the wafer bearing table along the direction vertical to the surface of the wafer bearing table is increased or reduced

By adopting the technical scheme, after the feeding mechanism is started, the grinding spindle and the grinding motor can be driven to move to reduce the distance between the grinding part and the surface of the bearing table, after the grinding part moves to the set grinding position, the feeding mechanism keeps the stability of the grinding part, and after the grinding is finished, the feeding mechanism drives the grinding part to move to increase the distance between the grinding part and the surface of the bearing table, so that the grinding part moves to the initial position.

Preferably, the grinding device comprises an upper slice box for placing slices to be ground, and the slices to be ground on the upper slice box are taken out and then placed into a slice loading position; the grinding device comprises a detection mechanism, a grinding mechanism and a grinding mechanism, wherein the detection mechanism is used for respectively detecting whether the sheet to be ground is on the sheet feeding box and the sheet bearing platform; the grinding machine comprises a main controller, wherein the main controller is in signal connection with a detection mechanism and controls the grinding unit and a workbench to be opened or closed;

detection step 1: when the detection mechanism detects that no sheet to be ground exists on the sheet feeding box and the sheet bearing table, the detection mechanism sends a signal to the main controller;

and a detection step 2: the main controller controls the grinding part on the grinding unit to rise to the initial position and stop rotating, and the workbench stops rotating

By adopting the technical scheme, when the detection mechanism detects that no wafer exists on the wafer loading box and the wafer bearing table, the main controller starts a stop program to control the grinding unit to rise to the initial position, stop rotating and close the workbench.

Preferably, the rotation speed of the wafer bearing platform is not more than 20rpm, and the rotation speed of the grinding part is 1000-6000 rpm.

By adopting the technical scheme, the yield of grinding the wafer is high under the condition of the rotating speed.

Preferably, the grinding device comprises an adsorption piece for placing the piece to be ground on the piece bearing table;

step 1: the adsorption piece moves to the position right above the upper surface of the to-be-ground sheet along the vertical direction;

and a step 2: adsorbing the to-be-ground sheet by the adsorption piece;

step 3: the adsorption piece moves to the position right above the chip loading position;

and step 4: when the wafer bearing table moves to the wafer loading position, the adsorption of the adsorption piece to the wafer to be ground is removed, and the wafer to be ground falls on the upper surface of the wafer bearing table rotating around the central line of the workbench.

Through adopting above-mentioned technical scheme, place the wafer to the wafer platform automatically, be convenient for reduce staff's work load, the breakage rate when the wafer is placed simultaneously is lower, improves the efficiency of wafer attenuate grinding, and the security is good.

Preferably, the device comprises a material taking device, wherein the material taking device comprises a transverse moving mechanism, a vertical moving mechanism and a blowing and sucking assembly;

the vertical mechanism drives the adsorption piece to move, the moving direction of the adsorption piece is perpendicular to the working surface on the wafer bearing table, and the transverse moving mechanism drives the adsorption piece to move, and the moving direction of the adsorption piece is parallel to the working surface on the wafer bearing table;

the blowing and sucking component can adsorb the piece to be ground and the adsorption part to be tightly connected, and the blowing and sucking component can apply a floating piece effect on the piece to be ground connected with the adsorption part.

By adopting the technical scheme, after the blowing and sucking assembly starts the air suction mode to adsorb the to-be-ground sheet, the transverse moving mechanism drives the to-be-ground sheet to move right above the sheet loading position, the vertical moving mechanism drives the to-be-ground sheet to move downwards, the distance between the to-be-ground sheet and the upper surface of the sheet bearing table is reduced, and when the sheet bearing table moves to the sheet loading position, the blowing and sucking assembly starts the blowing and sucking effect to enable the to-be-ground sheet to fall on the sheet bearing table.

Preferably, including main control unit, signal connection has the position finding mechanism on the main control unit, and the position finding mechanism is used for the rotational position of testing table, and main control unit can control the suction of suction subassembly.

By adopting the technical scheme, when the position measuring mechanism detects that the workbench rotates to a set position, the blowing and sucking assembly starts the blowing-off function, and the to-be-ground sheet can be accurately blown to the sheet bearing table positioned at the sheet loading position.

Preferably, the grinding device comprises an adsorption piece for taking off the finished grinding piece on the wafer bearing table; the device also comprises a lower sheet box which is fixedly arranged;

step 1: the adsorption piece moves to the position right above the upper surface of the finished grinding piece along the vertical direction;

and a step 2: adsorbing and grinding the finished product by the adsorption piece;

step 3: the adsorption piece moves to the right upper part of the lower film box;

and step 4: and removing the adsorption of the adsorption piece on the grinding finished product piece, and enabling the grinding finished product piece to fall to the lower wafer box.

Through adopting above-mentioned technical scheme, take off the wafer from the wafer bearing platform automatically, be convenient for reduce staff's work load, the breakage rate when the wafer takes off is lower simultaneously, improves the efficiency of wafer attenuate grinding, and the security is good.

In summary, the present application includes at least one of the following beneficial technical effects:

1. the wafer is thinned and ground in place by one-time grinding, repeated micro-grinding is not needed, meanwhile, the height of a grinding part is not needed to be adjusted for many times when one wafer is ground, the position of the grinding part needs to be lowered for about 10 times when one wafer is ground in the prior art, the scheme eliminates errors generated by descending a moving part every time, the grinding precision is higher, and meanwhile, when the grinding part grinds a plurality of wafers in a thinning manner, the position of the grinding part is kept unchanged, if the prior art needs to grind 100 wafers, the wafers can be divided into 25 groups, each group of four wafers, the grinding part needs to be accurately moved to a grinding distance of 25 times, and the scheme can move an accurate distance once to finish the thinning grinding of 100 wafers, and reduce errors caused by repeated reciprocating movement of the grinding part;

2. by adopting the automatic feeding and discharging method, the full-automatic grinding method is realized, the automation degree is high, and the production efficiency is greatly improved.

Drawings

FIG. 1 is a schematic structural view of a thin-ground portion of an embodiment;

FIG. 2 is a schematic structural diagram of the region positions of the workbench and the wafer carrier of the embodiment;

fig. 3 is a schematic diagram showing an automatic feeding and discharging structure of the embodiment.

Description of reference numerals: 1. a bed body; 11. touch operation of the display screen; 2. loading a sheet box; 3. a film discharging box; 4. a grinding unit; 41. grinding the main shaft; 43. grinding a workpiece; 44. grinding the motor; 45. a lead screw guide rail; 46. a feed motor; 5. a work table; 51. grinding positions; 52. a chip mounting position; 53. unloading the chip; 54. a wait bit; 6. a wafer bearing table; 61. a first stage; 62. a second stage; 63. a third stage; 64. fourthly, carrying out surface treatment; 65. a vacuum assembly; 71. an adsorbing member; 72. a lateral movement mechanism; 73. a vertical moving mechanism; 74. and a blowing and sucking component.

Detailed Description

The present application is described in further detail below with reference to figures 1-3.

The embodiment of the application discloses a multi-station full-automatic thinning and grinding method for semiconductor equipment.

Referring to fig. 1, the multi-station full-automatic thinning grinding method for the semiconductor equipment comprises a machine body 1, wherein a workbench 5 rotating around the axis of the workbench 1 is arranged on the machine body 1, four wafer bearing tables 6 used for being connected with a wafer to be ground are uniformly distributed on the workbench 5 along the circumferential direction of the workbench, and a grinding unit 4 is arranged on the machine body 1.

The more the sheet bearing tables 6 are, the more the number of the thinned sheets to be ground is, the higher the thinning efficiency is when the working table 5 rotates for one circle, but the more the sheet bearing tables 6 are, the more the connection or separation between any sheet bearing table 6 and the sheets to be ground needs to be controlled, the higher the cost is, the higher the control complexity is, meanwhile, the higher the speed requirement for taking and placing the sheets to be ground on the sheet bearing tables 6 is, and the higher the wear rate when the sheets to be ground are placed is; due to the arrangement of the three wafer bearing tables 6, when the working table 5 rotates for a circle, the thinning efficiency is reduced, the efficiency of the four wafer bearing tables 6 is high, and the cost is low.

The bed body 1 is provided with a touch operation display screen 11 for an operator to input grinding conditions and parameters. And the to-be-ground sheet after grinding is a grinding finished product. An upper wafer box 2 for placing a wafer to be ground and a lower wafer box 3 for placing a finished grinding part are detachably connected to the lathe bed 1. Comprises a main controller. The wafer to be ground is a diode wafer. The thickness of the sheet to be ground is 250 microns in this embodiment and the thickness of the finished ground part is 220 microns.

The grinding unit 4 includes a feed mechanism, a grinding spindle 41, and a grinding member 43. The feeding mechanism comprises a feeding motor 46 and a lead screw guide rail 45, the feeding motor 46 drives a lead screw of the lead screw guide rail 45 to rotate, a sliding block which moves on the lead screw guide rail 45 along the axis direction of the guide rail slides, the sliding direction of the sliding block on the lead screw guide rail 45 is vertical, the sliding block on the lead screw guide rail 45 is rotatably connected with the grinding spindle 41 through a bearing, and the sliding block on the lead screw guide rail 45 is fixedly connected with a grinding motor 44 which drives the grinding spindle 41 to rotate around the axis of the grinding spindle. The grinding member 43 is fixedly connected coaxially with the grinding spindle 41, and the grinding member 43 is fixed to the lower end of the grinding spindle 41. The vertical direction is the Z direction. The grinding member 43 is a grinding wheel in the present embodiment, and a grinding tool in another embodiment.

The rotation speed of the worktable 5 and the grinding member 43 can be set as required, and in this embodiment, the rotation speed of the wafer table 6 is 1rpm and the rotation speed of the grinding member 43 is 4800 rpm. In another embodiment, the rotation speed of the wafer stage 6 is not greater than 20rpm, and the rotation speed of the grinding member 43 is 1000 and 6000 rpm.

The feed motor 46 drives the grinding spindle 41 to move up and down in the Z direction. The grinding part 43 is driven to rotate by the rotation of the grinding spindle 41 to carry out thinning grinding on the to-be-ground sheet. After the distance between the grinding piece 43 and the wafer bearing table 6 is adjusted once, the to-be-ground wafers on the plurality of wafer bearing tables 6 can be ground.

From last down observation workstation 5, workstation 5 direction of rotation is anticlockwise, and 5 axes of workstation are along vertical direction, and the upper surface of workstation 5 is the working surface, and the upper surface level of workstation 5 sets up, and when grinding unit 4 ground the piece of waiting on the piece platform 6, workstation 5 continuously drives piece platform 6 and rotates.

When the workbench 5 rotates, the wafer bearing table 6 is driven to rotate around the rotating axis of the workbench 5, and the wafer bearing table 6 drives the wafer to be ground to move to the area contacting with the grinding part 43 to be a grinding position 51; the wafer carrying table 6 moves to a wafer loading position 52 which is an area for placing wafers to be ground on the wafer carrying table 6; the wafer bearing table 6 moves to a region where the wafer to be ground is unloaded from the wafer bearing table 6 to form a wafer unloading position 53; the wafer support table 6 is provided with a waiting position 54, and the waiting position 54 is located in the area between the wafer support table 6 moving from the grinding position 51 to the wafer unloading position 53.

The four wafer bearing platforms 6 are a first platform 61, a second platform 62, a third platform 63 and a fourth platform 64 respectively; the four stage supports 66 are identical in structure and function. The wafer bearing tables 6 are respectively provided with a vacuum assembly 65 which can be independently controlled, and each vacuum assembly 65 comprises a control unit, a vacuum valve, a compressed air valve, a vacuum channel and a compressed air channel; the control unit respectively controls the opening or closing of the vacuum valve and the compressed air valve independently, the vacuum valve is connected to the vacuum channel and used for controlling the opening or closing of the vacuum channel, the compressed air valve is connected to the compressed air channel and used for controlling the opening or closing of the compressed air channel, and the to-be-ground part can be adsorbed and floated through the control unit. In another embodiment, the wafer bearing table 6 is connected with the workpiece to be ground through a tool clamp.

The vacuum assembly 65 comprises porous ceramic arranged on the wafer bearing table 6, a plurality of micropores are formed in the porous ceramic to accommodate air flow, the porous ceramic comprises circular porous ceramic coaxial with the wafer bearing table and annular porous ceramic located outside the circular porous ceramic, the annular porous ceramic and the circular porous ceramic are arranged at intervals, the diameter of the circular porous ceramic is four inches, and the outer diameter of the annular porous ceramic is five inches. The porous ceramics can respectively correspond to two to-be-ground parts 43 with different diameters, the circular porous ceramics corresponds to a 4-inch to-be-ground part, the annular porous ceramics and the circular porous ceramics correspond to a 5-inch to-be-ground part, the 5-inch to-be-ground part accurately covers the surfaces of the annular porous ceramics and the circular porous ceramics, and in other embodiments, the annular porous ceramics with the outer diameter of six inches are arranged on the wafer bearing platform 6 according to design requirements. After the part 43 to be ground is accurately placed on the porous ceramic of the wafer bearing table 6, the part 43 to be ground can cover the corresponding porous ceramic on the wafer bearing table 6. The porous ceramics can be respectively communicated with a compressed air channel or a vacuum channel, the compressed air channel can blow air into the porous ceramics, and the vacuum channel can extract the air in the porous ceramics.

When the position of the workpiece 43 to be ground on the wafer bearing table 6 deviates, the corresponding porous ceramic is not covered by the workpiece 43 to be ground, the vacuum assembly 65 reports the error, and the equipment stops working. When the porous ceramics are communicated with the vacuum channel, the to-be-ground sheet can cover the corresponding porous ceramics on the sheet bearing table 6, the vacuum component 65 can tightly press and connect the to-be-ground sheet and the sheet bearing table 6, so that the relative position between the to-be-ground sheet and the sheet bearing table 6 is kept unchanged, and the stable connection between the to-be-ground sheet and the sheet bearing table 6 is realized; when the porous ceramic is communicated with the compressed air channel, the vacuum assembly 65 can blow air to the surface of the sheet to be ground so as to generate a floating sheet effect between the sheet to be ground and the sheet bearing platform 6.

In the process that the to-be-ground sheet on the sheet bearing table 6 moves from the sheet loading position 52 to the grinding position 51 and from the grinding position 51 to the sheet unloading position 53, the vacuum assembly 65 exerts an adsorption effect on the to-be-ground sheet, and the to-be-ground sheet is tightly connected with the sheet bearing table 6; when the bearing table moves to the wafer unloading position 53, the vacuum assembly 65 exerts a floating wafer effect on the wafer to be ground, and the vacuum assembly 65 exerts an acting force on the grinding part 43 to separate from the wafer bearing table 6.

Preferably, the device further comprises a detection mechanism, the detection mechanism is used for respectively detecting whether the upper cassette 2 and the wafer bearing table 6 are to be ground, the detection mechanism comprises a sensor positioned on the bottom surface of the inner cavity of the upper cassette 2, the sensor is used for measuring whether the upper cassette 2 is to be ground, the sensor is a pressure sensor in the embodiment, the detection mechanism comprises an induction piece used for detecting the vacuum degree of porous ceramics on the wafer bearing table 6, the induction piece is a component on the existing vacuum equipment, and when no wafer exists on the wafer bearing table 6, the porous ceramics on the wafer bearing table 6 cannot form vacuum; the main controller is in signal connection with the detection mechanism and controls the grinding unit 4 and the workbench 5 to be opened or closed. The main controller is connected with a buzzer through signals.

Detection step 1: when the detection mechanism detects that no piece to be ground exists on the upper piece box 2 and the piece bearing table 6, the detection mechanism sends a signal to the main controller.

And a detection step 2: the main controller controls the grinding part 43 on the grinding unit 4 and the workbench 5 to stop rotating, and the main controller controls the feeding motor 46 to rotate to drive the grinding part 43 to move upwards; and meanwhile, the buzzer is controlled to make a sound to prompt that the grinding of the wafer is finished.

The thinning grinding method comprises the following steps:

a. putting a plurality of wafers to be ground into the upper wafer box 2, inputting grinding parameters on the touch operation display screen 11, starting the grinding unit 4 and the feeding mechanism, enabling the grinding spindle 41 in the grinding unit 4 to drive the grinding piece 43 to rotate around the axis of the grinding spindle at a rotating speed of 4800rpm, and rapidly feeding the grinding piece to the height position of the set target thickness along the Z direction;

compressed air channels of the four wafer bearing tables 6 are opened, the workbench 5 rotates for a fixed angle, the first table 61 is rotated to the wafer loading position 52, and wafers to be ground are placed in the wafer bearing tables 6 on the wafer loading position 52.

b. After the detection mechanism detects that the loading position 52 of the workbench 5 is to be ground, the to-be-ground sheet is defined as a to-be-ground sheet a, the workbench 5 rotates at a set speed, in this embodiment, at a rotating speed of 1rpm, the to-be-ground sheet a adsorbed on the first table 61 is rotated from the loading position 52 to a grinding position 51 below the grinding piece 43, in the rotating process of the workbench 5, the lower surface of the grinding piece 43 is in contact with the surface of the to-be-ground sheet a, the to-be-ground sheet a is thinned and ground to a set target thickness in one step, and the to-be-ground sheet a is thinned and ground to be a finished grinding product.

c. When the second table 62 rotates to the chip loading position 52 by a fixed angle along with the workbench 5, another chip to be ground is placed on the second table 62 positioned at the chip loading position 52, the chip to be ground is defined as a chip b to be ground, meanwhile, a compressed air channel of the second table 62 is closed, a vacuum channel is opened, the chip b to be ground is adsorbed, enters the grinding position 51 along with the rotation of the workbench 5, and is ground in place at one time. At this time, the sheet a to be ground on the first table 61 is ground, and the process proceeds to the waiting position 54.

d. And placing another piece to be ground on the third table 63 positioned at the piece loading position 52, defining the piece to be ground at the position as a piece c to be ground, closing the compressed air channel of the third table 63, opening the vacuum channel, adsorbing the piece c to be ground, and conveying the piece c to be ground to the grinding position 51 along with the rotation of the workbench 5. At this time, the wafer b to be ground on the second table 62 is ground, and enters the waiting position 54. Another sheet to be ground is moved to a position above the loading position 52, and the sheet to be ground is defined as a sheet d to be ground.

e. The first table 61 rotates to the sheet unloading position 53 from the waiting position 54 along with the workbench 5, the vacuum channel of the first table 61 is closed, the compressed air channel is opened, the to-be-ground sheet a after grinding is grabbed, and the to-be-ground sheet a is placed into the lower sheet box 3. At the moment, the fourth table 64 rotates to the chip loading position 52 along with the workbench 5, the to-be-ground chip d is placed on the fourth table 64, meanwhile, the compressed air channel of the fourth table 64 is closed, the vacuum channel is opened, the to-be-ground chip d is adsorbed, and the to-be-ground chip d enters the chip grinding position along with the rotation of the workbench 5.

f. When the second table 62 is transferred from the waiting position 54 to the sheet unloading position 53, the vacuum channel of the second table 62 is closed, the compressed air channel is opened, the sheet b to be ground is grabbed, the sheet b to be ground is placed into the lower sheet box 3, and the sheet c to be ground of the third table 63 is located at the waiting position 54 after being ground for one time.

g. When the worktable 5 drives the third table 63 to rotate from the waiting position 54 to the sheet unloading position 53, the third table 63 is vacuum-closed, the compressed air channel is opened, the sheet c to be ground is grabbed, and the sheet c to be ground is placed in the lower sheet box 3.

h. At this time, the sheet d to be ground positioned on the table four 64 is ground once, the table four 64 is transferred from the grinding position 51 to the waiting position 54, and when the table four 64 is transferred from the waiting position 54 to the sheet unloading position 53 along with the table 5, the sheet d to be ground is grasped and placed in the lower cassette 3.

i. After the grinding process is started, the detection mechanism detects that the upper film box 2 is to be ground, and the automatic thinning grinding process is executed all the time.

j. When the detection mechanism detects that no sheet to be ground is arranged in the upper sheet box 2 and no sheet-bearing table 6 on the working table 5 adsorbs the sheet to be ground or a finished product to be ground, the grinding process is automatically finished. The workbench 5 stops rotating, the grinding piece 43 rises along the Z direction, the buzzer prompts that the grinding is finished, and an operator takes out the grinding finished product piece from the lower piece box 3.

The implementation principle of the multi-station full-automatic thinning and grinding method for the semiconductor equipment is as follows: to the attenuate grinding of wafer, once grinding targets in place, need not relapse trace grinding many times, the position of grinding piece 43 does not need adjustment height many times when accomplishing the grinding of a wafer simultaneously, has eliminated the error that descending motion part produced at every turn, and grinding precision is higher, and when grinding piece 43 carries out the attenuate grinding to a plurality of wafers simultaneously, grinding piece 43 position remains unchanged, and the attenuate grinding of a plurality of wafers just can be accomplished to portable accurate distance once, reduces the error that grinding piece 43 reciprocating motion caused many times.

The embodiment of the application also discloses an automatic feeding and discharging method.

Referring to fig. 3, an automatic feeding method comprises a suction member 71 for putting a sheet to be ground on the sheet receiving table 6 rotating about the rotation axis of the table 5 in the above-described scheme.

Step 1: the adsorption piece 71 moves to the position right above the upper surface of the to-be-ground sheet along the vertical direction; in the present embodiment, the gap between the suction member 71 and the sheet to be ground is any one of the gaps in the range of 0.5 to 5 mm, and preferably, the gap between the suction member 71 and the sheet to be ground is 0.5 mm.

And a step 2: the adsorbing member 71 adsorbs the sheet to be ground;

step 3: the adsorption piece 71 moves to the position right above the chip loading position 52, and the distance between the chip to be ground and the chip bearing table 6 is 0.5 mm;

and step 4: when the wafer bearing table 6 moves to the wafer loading position 52, the adsorption of the adsorption piece 71 to the wafer to be ground is removed, and the wafer to be ground falls on the upper surface of the wafer bearing table 6 rotating around the central line of the workbench 5.

The material taking device is connected to the lathe bed 1 and comprises a transverse moving mechanism 72, a vertical moving mechanism 73 and a blowing and sucking assembly 74; the main controller can control the blowing and the suction of the blowing and suction assembly 74 and control the movement of the transverse moving mechanism 72 and the vertical moving mechanism 73. The vertical mechanism drives the adsorption piece 71 to move, the moving direction of the adsorption piece is perpendicular to the working surface on the wafer bearing table 6, and the transverse moving mechanism 72 drives the adsorption piece 71 to move, and the moving direction of the adsorption piece is parallel to the working surface on the wafer bearing table 6; the blowing and sucking assembly 74 can adsorb and compress the piece to be ground and the adsorption piece 71, and the blowing and sucking assembly 74 can apply a floating piece effect on the piece to be ground connected with the adsorption piece 71.

The transverse moving mechanism 72 comprises a transverse fixing frame fixed on the bed body 1, a transverse guide rail is arranged on the transverse fixing frame, and a transverse conveying mechanism is arranged on the transverse fixing frame. The transverse conveying mechanism comprises a transverse conveying belt capable of transversely reciprocating. Fixedly connected with and transverse guide sliding connection's vertical mount on the horizontal conveyer belt, vertical mount is fixed and is provided with vertical pneumatic cylinder, and vertical direction removal different length can be followed fast to the output shaft of vertical pneumatic cylinder. The output shaft of pressure-vaccum subassembly 74 and vertical pneumatic cylinder, pressure-vaccum subassembly 74 includes the pressure-vaccum frame of fixing with the output shaft of vertical pneumatic cylinder, the flexible suction nozzle on the lower surface of adsorption piece 71 for being fixed in pressure-vaccum frame, the surface that has set firmly the flexible suction nozzle on the pressure-vaccum frame has set firmly distance sensor, distance sensor measures the surface that the pressure-vaccum frame is fixed with the flexible suction nozzle and to the distance of treating the piece of grinding of top in last film cassette 2, when adsorption piece 71 moves the distance that treats grinding piece 43 apart from and equals the measuring distance that distance sensor set for, the vertical pneumatic cylinder of main control unit control stops moving, pressure-vaccum subassembly 74 includes and controls the vacuum channel and the compressed air passageway that communicate respectively through the control unit with adsorption piece 71.

The device comprises a positioning mechanism in signal connection with a main controller, wherein the positioning mechanism is used for detecting the circumferential position of the rotation of the workbench 5. The position measuring mechanism is a zero sensor fixed on the workbench 5, when the workbench 5 rotates to a certain determined position, the zero sensor measures that the rotating angle of the workbench 5 is 0 degree, at the moment, the main controller controls the blowing and sucking assembly 74 of the blowing and sucking assembly 74 to be opened, and simultaneously controls the vacuum assembly 65 on the wafer bearing table 6 on the wafer loading position 52 to be opened, and the vacuum assembly 65 on the wafer bearing table 6 on the wafer unloading position 53 to be opened.

Referring to fig. 3, the adsorbing member 71 includes a first adsorbing flexible member for placing the to-be-ground member 43 on the wafer table 6, and the adsorbing member 71 further includes a second adsorbing flexible member for removing the ground wafer on the wafer table 6.

Step 1: the second adsorption flexible piece moves to a position right above the upper surface of the finished grinding piece along the vertical direction; the gap between the adsorption piece 71 and the piece to be ground is 0.5 mm, and in other implementations, the gap between the adsorption flexible piece II and the piece to be ground ranges from 0.5 mm to 5 mm;

and a step 2: adsorbing and grinding the finished product by the adsorption flexible part II;

step 3: the second adsorption flexible piece moves to the position right above the lower box 3, and when the grinding finished product piece is not placed in the lower box 3, the distance between the second adsorption flexible piece and the bottom surface of the lower box 3 is 10 mm; when the finished grinding parts are placed in the lower box 3, the distance between the second adsorption flexible part and the uppermost finished grinding part in the lower box 3 is the thickness of the finished grinding part of the lower box 3;

and step 4: the adsorption of two pairs of grinding finished products of the adsorption flexible piece is removed, and the grinding finished products fall into the lower film box 3.

The second adsorption flexible part adopts a driving mode the same as that of the first adsorption flexible part, namely, adsorption of moving and grinding finished parts is realized through the material taking device.

The implementation principle of the automatic feeding and discharging method in the embodiment of the application is as follows: by adopting an automatic feeding and discharging method, when the wafer bearing platform 6 moves from the wafer unloading position 53 to the wafer loading position 52, the material taking device finishes taking out the to-be-ground part 43 in the upper wafer box 2 once and moves to the position above the wafer loading position 52, when the position measuring mechanism detects that the wafer bearing platform 6 rotates to the wafer loading position 52, the to-be-ground part 43 and the adsorption part 71 are separated and fall onto the wafer bearing platform 6, and at the moment, the wafer bearing platform 6 is still in a rotating state; when the sheet bearing table 6 moves from the waiting position 54 to the sheet unloading position 53, the material taking device finishes once taking off the ground finished product on the sheet bearing table 6 positioned at the sheet unloading position 53 and then putting the ground finished product into the lower sheet box 3. The full-automatic grinding method is realized, the automation degree is high, and the production efficiency is greatly improved;

in the whole process, an operator only needs to place a workpiece into the upper film box 2, set parameters, and finish other processes by equipment, and when the system detects that no wafer is in the upper film box 2 and no wafer is adsorbed by the four wafer bearing tables 6 on the workbench 5, the grinding process is automatically finished; the security is strong, and operating personnel can monitor many equipment simultaneously, practices thrift the cost greatly.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims (9)

1. A multi-station full-automatic thinning grinding method for semiconductor equipment comprises a grinding unit (4), a workbench (5), and a plurality of wafer bearing tables (6) arranged on the workbench (5), wherein the wafer bearing tables (6) drive a wafer to be ground to move to a grinding position (51) in a region contacting with a grinding part (43); the wafer bearing table (6) moves to a wafer loading position (52) which is an area for placing the wafer to be ground on the wafer bearing table (6); the wafer bearing table (6) moves to a region for unloading the wafers to be ground from the wafer bearing table (6) to form a wafer unloading position (53); the grinding piece to be ground after grinding is a grinding finished product; the method is characterized in that: the workbench (5) drives the wafer bearing table (6) to rotate circumferentially, and the workbench (5) drives the wafer bearing table (6) to sequentially move from the wafer loading position (52) to the grinding position (51) and from the grinding position (51) to the wafer unloading position (53); in the process that the to-be-ground sheet on the sheet bearing table (6) moves from the sheet loading position (52) to the grinding position (51) and from the grinding position (51) to the sheet unloading position (53), the to-be-ground sheet is tightly connected with the sheet bearing table (6);

the grinding unit (4) is provided with a grinding part (43) for grinding the to-be-ground sheet, the grinding unit (4) can drive the grinding part (43) to rotate, and the rotating speed of the grinding part (43) is 1000-6000 rpm; the distance between the grinding part (43) and the wafer bearing table (6) can be adjusted and moved to be kept stable; after the distance between the grinding piece (43) and the wafer bearing table (6) is adjusted once, the grinding piece (43) can finish grinding of the wafer to be ground on the wafer bearing table (6);

when the grinding unit (4) grinds a to-be-ground sheet on the sheet bearing table (6), the working table (5) continuously drives the sheet bearing table (6) to move, and the rotating speed of the sheet bearing table (6) is not more than 20 rpm;

step 1: the workbench (5) drives the wafer bearing table (6) to rotate around a rotating shaft of the workbench (5), the grinding unit (4) drives the grinding part (43) to rotate around the rotating shaft of the grinding part (43), and the distance between the grinding part (43) and the opposite surface of the wafer bearing table (6) of the grinding position (51) is adjusted to be the thickness of a grinding finished product;

and a step 2: placing the sheet to be ground in a loading position (52);

step 3: the workbench (5) drives the wafer bearing table (6) of the wafer loading position (52) to rotate to the grinding position (51);

and step 4: the grinding piece (43) grinds the to-be-ground sheet rotating around the rotating shaft of the workbench (5);

step 5: the workbench (5) drives the wafer bearing table (6) of the grinding position (51) to rotate to a wafer unloading position (53);

step 6: the finished grinding part is removed from the chip removal position (53).

2. The multi-station full-automatic thinning grinding method for the semiconductor equipment according to claim 1, characterized in that: a vacuum assembly (65) is arranged on the wafer bearing table (6), and the vacuum assembly (65) comprises a control unit for controlling the opening or closing of a vacuum channel and a compressed air channel;

a connecting step 1: in the process that the to-be-ground sheet on the sheet bearing table (6) moves from the sheet loading position (52) to the grinding position (51) and from the grinding position (51) to the sheet unloading position (53), the vacuum assembly (65) exerts an adsorption effect on the to-be-ground sheet, and the to-be-ground sheet is tightly connected with the sheet bearing table (6);

a connecting step 2: when the bearing table moves to the chip unloading position (53), the vacuum assembly (65) exerts a floating chip effect on the finished grinding product, and the vacuum assembly (65) exerts an acting force separated from the bearing table (6) on the finished grinding product.

3. The multi-station full-automatic ironing grinding method for the semiconductor equipment according to claim 1, characterized in that: the grinding unit (4) further comprises a grinding spindle (41), a grinding motor (44) and a feeding mechanism; the grinding spindle (41) is fixedly connected with the grinding piece (43), the grinding motor (44) drives the grinding spindle (41) to rotate, and the feeding mechanism drives the grinding spindle (41) to move so that the distance between the grinding piece (43) and the wafer bearing table (6) along the direction perpendicular to the surface of the wafer bearing table (6) is increased or decreased.

4. The multi-station full-automatic ironing grinding method for the semiconductor equipment according to claim 1, characterized in that: comprises an upper slice box (2) for placing slices to be ground, wherein the slices to be ground on the upper slice box (2) are taken out and then placed into a slice placing position (52); the grinding device comprises a detection mechanism, wherein the detection mechanism is used for respectively detecting whether the upper sheet box (2) and the sheet bearing platform (6) are to be ground or not; the grinding machine comprises a main controller, wherein the main controller is in signal connection with a detection mechanism and controls the grinding unit (4) and a workbench (5) to be opened or closed;

detection step 1: when the detection mechanism detects that no sheet to be ground exists on the upper sheet box (2) and the sheet bearing table (6), the detection mechanism sends a signal to the main controller;

and a detection step 2: the main controller controls the grinding piece (43) on the grinding unit (4) to rise to the initial position and stop rotating, and the workbench (5) stops rotating.

5. The multi-station full-automatic thinning grinding method for the semiconductor equipment according to claim 1, characterized in that: comprises an absorption piece (71) used for placing a piece to be ground on a piece bearing platform (6);

step 2.1: the adsorption piece (71) moves to the position right above the upper surface of the to-be-ground sheet along the vertical direction;

step 2.2: the adsorption piece (71) adsorbs the piece to be ground;

step 2.3: the adsorption piece (71) moves to the position right above the chip loading position (52);

step 2.4: when the wafer bearing table (6) moves to the wafer loading position (52), the adsorption of the adsorption piece (71) to the wafer to be ground is removed, and the wafer to be ground falls on the upper surface of the wafer bearing table (6) rotating around the central line of the workbench (5).

6. The multi-station full-automatic thinning grinding method for the semiconductor equipment according to claim 5, characterized in that: the device comprises a material taking device, wherein the material taking device comprises a transverse moving mechanism (72), a vertical moving mechanism (73) and a blowing and sucking assembly (74);

the vertical mechanism drives the adsorption piece (71) to move, the moving direction of the adsorption piece is vertical to the working surface on the wafer bearing table (6), and the transverse moving mechanism (72) drives the adsorption piece (71) to move, and the moving direction of the adsorption piece is parallel to the working surface on the wafer bearing table (6);

the blowing and sucking assembly (74) can adsorb and compress the piece to be ground and the adsorption piece (71) and is connected with the blowing and sucking assembly (74) can apply a floating piece effect on the piece to be ground connected with the adsorption piece (71).

7. The multi-station full-automatic ironing grinding method for the semiconductor equipment according to claim 5, characterized in that: the automatic blowing and sucking device comprises a main controller, wherein a position measuring mechanism is connected to the main controller through a signal and used for detecting the rotating position of a workbench (5), and the main controller can control blowing and sucking of a blowing and sucking assembly (74).

8. The multi-station full-automatic ironing grinding method for the semiconductor equipment according to claim 5, characterized in that: the material taking device comprises a lathe bed (1), wherein a workbench (5) and a grinding unit (4) are arranged on the lathe bed (1), and the material taking device is connected with the lathe bed (1).

9. The multi-station full-automatic ironing grinding method for the semiconductor equipment according to claim 1, characterized in that: comprises a suction piece (71) used for taking off the finished grinding piece on the wafer bearing table (6); the device also comprises a lower box (3) which is fixedly arranged;

step 3.1: the adsorption piece (71) moves to the position right above the upper surface of the finished grinding piece along the vertical direction;

step 3.2: the adsorption piece (71) adsorbs and grinds the finished product;

step 3.3: the adsorption piece (71) moves to the position right above the lower film box (3);

step 3.4: the adsorption of the adsorption piece (71) to the grinding finished product piece is removed, and the grinding finished product piece falls into the lower film box (3).

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