JP5153205B2 - Laser marking device - Google Patents

Description

  The present invention relates to a scanning-type laser marking technique, and more particularly to a laser marking apparatus capable of selectively or simultaneously performing normal marking and reduced marking.

  Scanning laser marking irradiates a workpiece with a laser beam condensed at a high density, shakes the laser beam with a scanning mirror, scans the spot of the laser beam on the surface of the workpiece, Marking (marking) by drawing a desired pattern such as letters, figures, symbols, etc. while instantaneously modifying (melting, evaporating, discoloring, etc.) a minute portion of the surface of the workpiece that has been spotted with laser energy Or printing).

  Scanning laser marking devices have been widely used for marking for electronic parts such as LSIs, but recently, marking for ultra-small semiconductor packages such as CSP (Chip Size Package) is also required.

  In the CSP, there are two types of applications: marking the production management information such as a lot number on the back side of the package with a normal size, and marking the product information such as an ID on the front side of the package with a very small size. Here, since the marking process on the back surface of the package can use almost the entire surface (for example, several mm square) of the back surface of the chip (silicon substrate) as a marking area, it can be sufficiently handled by a conventional general laser marking device for electronic components. However, the marking process on the front surface of the package is performed by finely marking a part or one corner of the chip main surface with a size of, for example, 100 μm square, and a conventional laser marking apparatus can obtain a required resolution (10 μm or less). Therefore, a high-resolution type special laser marking device specialized for fine marking is used.

  As described above, conventionally, two types of laser marking devices are required for CSP double-side marking as an example.

  The present invention has been made in view of the circumstances of the prior art, and an object of the present invention is to provide a laser marking apparatus that can perform both normal marking and reduced (fine) marking with a single unit.

In order to achieve the above object, a first laser marking apparatus of the present invention is a laser marking apparatus that marks a desired pattern by irradiating a workpiece with a laser beam by a scanning method. A stage supported at a predetermined position, a laser oscillation unit that oscillates and outputs a marking laser beam, a scan mirror that reflects the laser beam from the laser oscillation unit toward the workpiece on the stage, and A condensing lens that condenses the laser light from the scan mirror at a position of a predetermined focal length, and rotationally displaces the scan mirror to change the irradiation position of the laser light on the workpiece. a laser scanning unit for optically scanning a first position to interrupt the laser beam path between the two while maintaining the distance interval at a constant between said laser scanning unit stage The possess movably and reduction optical system provided between a second position retracted from the laser beam path, it said reduced when the optical system is disposed in the second position, the laser scanning unit When the laser beam exiting the laser beam is directly focused on the workpiece and a desired pattern is marked without being reduced, and the reduction optical system is disposed at the first position, the laser The laser beam emitted from the scanning unit is once focused in the reduction optical system and then condensed again on the workpiece, and a desired pattern is reduced and marked with a desired reduction rate.

In the above-described apparatus configuration, the reduction optical system for reducing the pattern at a desired reduction ratio interrupts the laser light path between the two while keeping the distance between the laser scanning unit and the stage constant. It is provided to be movable between a position and a second position retracted from the laser beam path.
When performing normal marking, the reduction optical system is retracted to the second position. In this case, the laser beam emitted from the laser scanning unit travels straight in the air and is condensed at the focal point determined by the focal length of the condensing lens of the laser scanning unit, that is, the processing point of the workpiece on the stage. A normal or standard size marking dot is formed at the position. By scanning operation of the laser scanning unit, a desired pattern can be formed in a normal size by connecting marking dots on the surface of the workpiece.

When performing fine marking, the reduction optical system is moved to the first position and inserted between the laser scanning unit and the stage. In this case, the laser beam emitted from the laser scanning unit under the same conditions as in normal marking passes through the reduction optical system, and once focused in the reduction optical system, the processing point of the workpiece on the stage Then, the light is condensed again, and a marking dot of reduced size or fine size is formed at the irradiation position. By scanning operation of the laser scanning unit, a desired pattern can be formed in a fine size by connecting marking dots on the surface of the workpiece.

  In this way, one unit can be used without changing software or adjusting the control system by simply putting the reduction optical system in and out of the optical path between the laser scanning unit and the stage while keeping the distance between the laser scanning unit and the stage constant. Thus, normal marking and reduced (fine) marking can be selectively performed.

As a preferred aspect, a unit main body that supports or accommodates the reduction optical system, and a movement that moves the unit main body to move the reduction optical system between the first position and the second position. A mechanism and a control system for controlling the operation of the moving mechanism are provided. According to such a configuration, it is possible to improve the accuracy, reproducibility, and operability of the forward / backward movement operation and the alignment operation of the reduction optical system as described above.

A second laser marking apparatus of the present invention is a laser marking apparatus that marks a desired pattern by irradiating a workpiece with a laser beam by a scanning method, a stage for supporting the workpiece at a predetermined position, and a marking A laser oscillation unit that oscillates and outputs a laser beam for use, a scan mirror that reflects the laser beam from the laser oscillation unit toward the workpiece on the stage, and the laser beam from the scan mirror And a condensing lens that condenses the laser beam at a predetermined focal length , and a laser scanning unit that optically scans an irradiation position of the laser beam on the workpiece by rotationally displacing the scan mirror The laser scanning unit is disposed between the laser scanning unit and the stage so as to be interposed only in a part of the maximum marking range that can be scanned by the laser scanning unit. In the region where the reduction optical system is not interposed in the maximum marking range, the laser beam emitted from the laser scanning unit is directly condensed on the workpiece to be desired. In the area where the reduction optical system is interposed in the maximum marking range, the laser beam emitted from the laser scanning unit is once focused in the reduction optical system. The light is condensed again on the workpiece, and a desired pattern is reduced and marked with a desired reduction ratio.

In the above apparatus configuration, in the region where the reduction optical system is not interposed in the maximum marking range, the laser light emitted from the laser scanning unit travels straight in the air avoiding the reduction optical system, and at the focal length of the condenser lens. Directly focusing on a fixed focal position, that is , a processing point on the stage, a normal size marking dot or a desired pattern is formed. In the region where the reduction optical system is interposed in the maximum marking range, the laser beam emitted from the laser scanning section passes through the reduction optical system, and once focused in the reduction optical system, another laser beam on the stage The light is condensed again at the processing point to form fine-sized marking dots or a desired pattern. According to such a marking area dividing function, either normal marking or fine marking can be selected by selecting a marking area, and normal marking and fine marking can be mixed and performed simultaneously.

  According to a preferred aspect of the present invention, the reduction optical system has a plurality of folding mirrors arranged in a predetermined relative positional relationship, and sequentially applies the laser light from the laser scanning unit to the plurality of folding mirrors. A reflection optical system that folds back and extends the laser optical path length between the scanning unit and the stage by a predetermined distance, and has a constant reduction magnification, and reduces the laser light from the reflection optical system onto the workpiece. And a reduction lens optical system for focusing.

  In this case, more preferably, the reflection optical system includes first, second, third, and fourth folding mirrors, and the first folding mirrors emit laser light that travels straight in a substantially vertical direction from the laser scanning unit. Reflected in the substantially horizontal direction toward the second folding mirror, and the second folding mirror reflected in the substantially vertical direction toward the third folding mirror the laser light traveling straight in the substantially horizontal direction from the first folding mirror. And the third folding mirror reflects the laser beam traveling straight in the substantially vertical direction from the second folding mirror toward the fourth folding mirror in the substantially horizontal direction, and the fourth folding mirror performs the third folding mirror. Laser light that travels straight in a substantially horizontal direction from the mirror is reflected in a substantially vertical direction toward the reduction lens optical system. According to such a configuration, the laser light path in the reflection optical system takes a rectangular shape in the vertical plane, and the laser light path length can be kept most efficiently and constant with respect to the scanning operation of the laser beam by the laser scanning unit.

  According to a preferred aspect, the reduction optical system is provided with an optical path length adjusting unit for adjusting the optical path length of the laser light. This optical path length adjustment part is comprised by the mirror horizontal position adjustment part for adjusting the position of the one part or all part folding mirror in a horizontal direction as one preferable aspect.

  According to a preferred aspect, the reduction optical system is provided with a neutral density filter such as an ND filter. By attenuating the amount of laser light with this neutral density filter, the laser energy can be adjusted to an appropriate amount equivalent to that for normal marking even if the laser light is reduced and focused on the surface of the workpiece. Can do.

  As a preferred embodiment, the reduction lens optical system may be configured by a microscope lens. The stage preferably includes an XY stage mechanism for moving and positioning a workpiece in an arbitrary direction within a horizontal plane. As the laser light, a wavelength of 350 nm to 550 nm is preferably used, and specifically, a second harmonic or a third harmonic of ND: or Nd: YV04 is preferably used. A galvanometer mirror is preferably used as the scan mirror, and an fθ lens is preferably used as the condensing lens of the laser scanning unit.

  According to the laser marking apparatus of the present invention, the normal marking and the reduced (fine) marking can be combined and performed with one unit easily and efficiently by the configuration and operation as described above.

  Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

  1 to 4 show the configuration of a scanning laser marking device according to the first embodiment. Of these figures, FIGS. 1 and 3 show the system configuration of the entire apparatus, and FIGS. 2 and 4 show the configuration of the main optical system in the apparatus.

  This laser marking apparatus includes a reduction optical unit for fine marking in addition to general apparatus configurations such as a control power supply unit 10, a laser oscillation unit 12, a scanning head 14, an operation panel 16, a processing table 18, a power chamber 20, and the like. 32.

  In the basic configuration of this laser marking apparatus, the control power supply unit 10 mainly includes a control board (not shown) and the like, and an operation panel (for example, a keyboard) 16 and a display 22 are provided around it. The laser oscillation unit 12 incorporates, for example, a Q switch pulse type laser oscillator 24 and an excitation unit (not shown). The scanning head 14 contains or is equipped with a pair of (X, Y) galvanometer mirrors 26X, 26Y and an fθ lens (a condensing lens having distortion characteristics) 28 arranged orthogonal to each other, and a laser oscillation unit Twelve exits are integrally coupled. An XY stage 30 that can be moved and positioned in the XY direction in a horizontal plane is provided on the processing table 18 directly opposite to the exit of the scanning head 14. The workpiece W is placed on the XY stage 30. The utility chamber 20 accommodates power system components, circuit boards, chiller devices (not shown), and the like.

  The reduction optical unit 32 is installed in the vicinity of the processing table 18, for example, under the laser oscillation unit 12, so as to be movable in the horizontal direction. The specific configuration and operation of the reduction optical unit 32 will be described in detail later.

  When normal marking is performed in this laser marking apparatus, that is, when a pattern is marked on the workpiece W on the XY stage 30 with a normal size of, for example, 1 mm or more, as shown in FIGS. Is retracted to the side original position (return position) that is not placed on the XY stage 30.

  In this case, the pulse laser beam LB oscillated and output from the laser oscillator 24 is sequentially reflected in the scanning head 14 at a reflection angle corresponding to each rotation angle (swing angle) of the galvanometer mirrors 26X and 26Y, and then the fθ lens. 28 is emitted substantially vertically downward, travels straight in the air as it is, and is collected on the surface of the workpiece W on the XY stage 30, and one irradiation dot (focus position) with a dot size of, for example, about 50 μm. Marking dots are formed. By repeating laser marking in units of pulses as described above many times while controlling the rotation angle of both galvanometer mirrors 26X and 26Y, a desired pattern is formed in a desired size of 1 mm or more by connecting the marking dots in a line. can do.

  When performing fine marking in this laser marking apparatus, that is, when marking a pattern with a minute size of, for example, 100 μm or less on the workpiece W on the XY stage 30, the reduction optical unit 32 is provided as shown in FIGS. It is moved (advanced) forward from the original position to be positioned (intervened) between the scanning head 14 and the XY stage 30. Here, the distance between the scanning head 14 and the XY stage 30 may be the same as that in the normal marking, and need not be changed. In order to move the reduction optical unit 32 forward and backward between the original position (reverse movement position) and the forward movement position, for example, a robot hand 34 or a linear actuator with a guide rail that operates under the control of the control system. May be used.

  In the fine marking mode, the pulsed laser beam LB oscillated and output from the laser oscillator 24 is rotated at each rotation angle (running angle) of the galvanometer mirrors 26X and 26Y in the scanning head 14 in the same manner as in the normal marking mode. The light is sequentially reflected at a corresponding reflection angle and then emitted through the fθ lens 28 substantially vertically downward. However, the pulse laser beam LB exiting the scanning head 14 enters the reduction optical unit 32, passes through the optical path of a reflection optical system to be described later inside the unit, and then exits at the lower end of the unit (reduction lens optical system). 42 exits vertically below and is focused on the surface of the workpiece W on the XY stage 30 to form one marking dot with a dot size of, for example, about 5 μm at the irradiation position (focal position). Also in this case, by repeating the laser marking in units of pulses as described above many times while controlling the rotation angle of both the galvanometer mirrors 26X and 26Y, the fine marking dots are connected in a linear shape, even with a size of 100 μm or less. A desired pattern can be drawn with high definition.

  As described above, in this laser marking apparatus, the arrangement of the reduction optical unit 32 is maintained while keeping the distance between the scanning head 14 and the XY stage 30 (that is, the working distance from the fθ lens 28 to the XY stage 30) constant. Just by switching the position (reverse / forward position), there is no need to change the software or adjust the control system, and the normal marking mode suitable for the normal size of 1 mm or more and the fine size of 100 μm or less with one unit. It is possible to freely and selectively carry out fine marking suitable for the above.

  Therefore, any one of the normal marking and the fine marking can be applied to an arbitrary workpiece W, and both the markings can be easily mixed. In the case of the mixed type, the function of shifting the marking position on the workpiece W by the XY stage 30 can be suitably used.

  For example, in a double-side marking application for CSP, a silicon wafer may be placed on the XY stage 30 as the workpiece W, and marking may be performed in the wafer state. In this case, when normal marking is performed on the back surface of the CSP chip, the silicon wafer W is placed on the XY stage 30 with the back surface of the substrate facing up, and the reduction optical unit 32 is retracted to the original position (return position). Then, a pattern such as a lot number may be marked with a normal size on the back surface of each chip by a step-and-repeat method in which step movement by the XY stage 30 is repeated for each chip. Further, when fine marking is performed on the CSP chip main surface, the silicon wafer W is placed on the XY stage 30 with the substrate main surface (circuit pattern surface) facing up, and the reduction optical unit 32 is moved to the forward movement position. And inserted between the scanning head 14 and the XY stage 30. Then, a pattern such as an ID can be marked in a fine size at one corner of each chip main surface by the step-and-repeat method.

  The laser beam oscillated and output from the laser oscillator 24 may be either a fundamental wave or a harmonic wave of a solid-state laser, and is not limited to a pulsed laser beam but may be a continuous wave laser beam. Alternatively, the laser oscillator 24 can be replaced with another type of laser such as a semiconductor laser. In particular, it is desirable that laser light for a silicon substrate such as CSP has a wavelength of 350 nm to 550 nm, which is excellent in absorption rate by a silicon wafer (or chip) and can easily produce a desired optical system. Specifically, the second harmonic or the third harmonic of ND: YAG or Nd: YV04 can be preferably used.

  FIG. 5 shows a specific configuration example of the reduction optical unit 32. The reduction optical unit 32 of this configuration example has a rigid housing or unit main body 36. In this housing 36, a reflection optical system 38 for extending the optical path, a light reduction filter 40 for attenuating the laser light amount, and a reduction collection. The optical reduction lens optical system 42 is disposed at a predetermined position.

  The reflection optical system 38 includes four folding mirrors 44, 46, 48, and 50. Here, the first folding mirror 44 is disposed immediately below the emitting portion (fθ lens 28) of the scanning head 14 with the reflecting surface inclined obliquely upward with an inclination of 45 ° with respect to the horizontal axis or the vertical axis. Yes.

  The second folding mirror 46 is spaced apart from the first folding mirror 44 by a predetermined distance (Da) in the horizontal direction so as to oppose the reflecting surface of the first folding mirror 44 in the horizontal direction. The reflecting surface is arranged obliquely downward with an inclination of 45 ° with respect to the vertical axis.

  The third folding mirror 48 is spaced apart from the second folding mirror 46 by a predetermined distance (Db) in the vertical direction so as to face the reflecting surface of the second folding mirror 46 in the vertical direction. The reflecting surface is arranged obliquely upward with an inclination of 45 ° with respect to the vertical axis.

  The fourth folding mirror 50 is separated from the third folding mirror 48 by a predetermined distance interval (Dc) in the horizontal direction so as to face the reflecting surface of the third folding mirror 48 in the horizontal direction or The reflecting surface is arranged obliquely downward with an inclination of 45 ° with respect to the vertical axis.

  Normally, the fourth folding mirror 50 comes to a position directly below the first folding mirror 44, and the relationship of Da = Dc and Db = Dd is established. Here, Dd represents a distance interval between the first folding mirror 44 and the fourth folding mirror 50.

  The neutral density filter 40 is composed of, for example, an ND filter, and can be disposed at any position as long as it is on the laser optical path around the reflective optical system 38, but preferably the first folding mirror 44 and the second folding mirror 46. Between.

  The reduction lens optical system 42 is preferably a microscope lens having a constant reduction magnification obtained by combining a plurality of lenses 52, and is separated from the final stage (fourth) folding mirror 50 by a predetermined distance in the vertical direction. Thus, the optical axis is vertically aligned so as to face the reflecting surface of the mirror 50 in the vertical direction, and the mirror 50 is attached to the emission portion at the lower end of the unit.

  In the reduction optical unit 32, the laser beam LB emitted from the upper scanning head 14 toward the workpiece W on the XY stage 30 is an opening (laser introduction port) provided on the upper surface of the unit body 36. Enter the unit from 36a.

  In the unit 32, the first folding mirror 44 reflects the laser beam LB, which travels straight in the substantially vertical direction from the fθ lens 28 of the scanning head 14, toward the second folding mirror 46 in the horizontal direction.

  The second folding mirror 46 reflects the laser beam LB, which travels straight in the horizontal direction from the first folding mirror 44, toward the third folding mirror 48 in the vertical direction. Note that the laser beam LB passes through the ND lens 42 in the optical path between the first folding mirror 44 and the second folding mirror 46, and the amount of light is attenuated to about 1/10, for example.

  The third folding mirror 48 reflects the laser light LB that travels straight in the vertical direction from the second folding mirror 46 toward the fourth folding mirror 50 in the horizontal direction. The fourth folding mirror 50 reflects the laser beam LB, which travels straight in the horizontal direction from the third folding mirror 48, toward the reduction lens optical system 40 in the vertical direction.

  The reduction lens optical system 42 reduces the condensed laser beam LB on the workpiece W by narrowing the laser beam LB, which is linearly incident from the fourth folding mirror 50 and incident at a predetermined reduction magnification (for example, 1/20). Let

  Although the condensing point on the workpiece W is a micro area on the order of μm, the power of the laser beam LB is moderately attenuated by the neutral density filter 40, so that it is fine with a laser energy that is almost the same as that in normal marking. Marking dots are formed. This eliminates the need for adjustment to lower the laser oscillation output on the control power supply unit 10 or laser oscillation unit 12 side for fine marking. That is, the optimum excitation power for the laser oscillation operation of the laser oscillator 24 can be maintained and selected.

  In the reflection optical system 38, some transmitted light (leakage light) may be generated by the folding mirrors 44-50. Among them, the leaked light MB emitted from the first folding mirror 44 may enter the fourth folding mirror 50 directly below from the back surface and enter the reduction lens optical system 42. In that case, as shown in the figure, by arranging the light shielding plate 54 between the first folding mirror 44 and the fourth folding mirror 50, the mixing of the leaked light MB can be completely cut off.

  As described above, even when fine marking is performed, the laser beam LB is emitted from the scanning head 14 toward the workpiece W on the XY stage 30 under the same conditions as in normal marking. However, since the laser beam LB passes or passes through the reflection optical system 38 and the reduction lens optical system 42 in the reduction optical unit 32, the surface of the workpiece W on the XY stage 30 is the same as that for normal marking. The laser beam LB is condensed by reducing the beam diameter to a predetermined reduction ratio at the focal position, thereby forming fine-sized marking dots or patterns.

  Here, in the reflective optical system 38, the focal position of the fine marking is set to the focal position of the normal marking in accordance with the beam diameter of the laser beam LB emitted from the scanning head 14, the reduction magnification of the reducing lens optical system 42, and the like. The optical path length of the laser is set so as to match. In this embodiment, the optical path length adjusting unit 56 for setting / adjusting the laser optical path length is provided with means for displacing or finely adjusting the positions of the second and third folding mirrors 46 and 48 in the horizontal direction. .

FIG. 6 is an optically equivalent development view in which all the laser light paths bent by the respective folding mirrors 44 to 50 in the reflection optical system 38 are straightly connected in the vertical direction. In the drawing, the folding mirrors 44 to 50 of the reflection optical system 38 are omitted. As can be clearly seen from this vertical development view, the laser beam LB emitted from the scanning head 14 is once focused on the position S ₁ on the optical path in the reflection optical system 38 determined by the focal length of the fθ lens 28 (first). However, since there is no object there, it propagates on the optical path at a certain divergence angle and enters the demagnifying lens optical system 42, which is determined by the focal length of the demagnifying lens optical system 42, that is, the XY stage. A focal point (second focal point) is formed at the machining point S ₂ of the workpiece W on the workpiece 30.

Optically, the first focal position S ₁ corresponds to a single focal position in normal marking, that is, the position of the processing point S _C of the workpiece W on the XY stage 30. The optical path length in the reflecting optical system 38 or the arrangement of the folding mirrors 44 to 50 so as to give an optical extension distance interval DH between the first focal position S ₁ and the second focal position temporary focal position S _2. The position is set.

  7 and 8 show the configuration of the main part of the laser marking device according to the second embodiment of the present invention. In the figure, parts having substantially the same configuration or function as the apparatus configuration of the first embodiment described above are denoted by the same reference numerals.

  The second embodiment is characterized in that a reduction optical system corresponding to the reduction optical unit 32 described above is regularly fixed and arranged between the scanning head 14 and the XY stage 30. However, as clearly shown in FIG. 8, the reduction optical system 32 is disposed so as to be limitedly interposed only in a partial area Ea of the maximum marking range ME that can be scanned by the scanning head 14 in plan view.

In such a configuration, in the normal marking region Eb where the reduction optical system 32 is not interposed in the maximum marking range MA, the laser beam LB emitted from the scanning head 14 travels straight down in the air vertically avoiding the reduction optical system 32. Then, the light is directly focused on one processing point S _C of the workpiece W on the XY stage 30 to form a normal size marking dot or a desired pattern. Further, in the fine marking region Ea in which the reduction optical system is interposed in the maximum marking range, the laser beam LB emitted from the scanning head 14 is reduced by the reduction optical system 32 (reflection optical system 38, reflection optical system 38, as in the first embodiment). Light is condensed on another processing point S2 of the same workpiece W via the ND filter 40 and the reduction lens optical system 42) to form fine-sized marking dots or a desired pattern.

  With the marking region dividing function as described above, only normal marking is performed on a given workpiece W using the normal marking region Eb, or only fine marking is performed using the fine marking region Ea. It is also possible to perform both normal marking and fine marking simultaneously in a time-sharing manner using both the normal marking area Eb and the fine marking area Ea.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the technical idea.

  For example, in the reduction optical system or the reduction optical unit 32, the reflection optical system 38 is tilted to 45 ° in a predetermined direction by turning the four folding mirrors 44, 46, 48, and 50 as in the above-described embodiment. It is possible to form a laser beam path with the most efficient configuration and stable optical path length. In this regard, although not shown in the figure, the reflection optical system 38 can be configured by three or five or more folding mirrors, although it is accompanied by a decrease in efficiency or stability. Although the reduction magnification is reduced, the reduction lens optical system 42 can be simplified with a single lens.

  The laser marking device of the present invention can also be applied or applied to fine processing such as metal thin film peeling processing.

It is a perspective view which shows the whole structure (normal marking mode) of the laser marking apparatus in the 1st Embodiment of this invention. It is a schematic side view which shows the structure of the optical system in the laser marking apparatus of FIG. It is a perspective view which shows the whole structure (fine marking mode) of the laser marking apparatus in the said 1st Embodiment. It is a schematic side view which shows the structure of the optical system in the laser marking apparatus of FIG. It is a schematic sectional drawing which shows the specific structural example of the reduction optical unit in the said embodiment. It is the optical equivalent figure which expand | deployed the laser beam path of the reflective optical system in the reduction optical unit in the said embodiment to the perpendicular direction. It is a schematic sectional drawing which shows the structure of the principal part of the laser marking apparatus in 2nd Embodiment. It is a figure which shows the division of the normal marking area | region / fine marking area | region within the maximum marking range in the said 2nd Embodiment by planar view.

Explanation of symbols

10 Control power supply unit 12 Laser oscillation unit
14 Scanning head 18 Processing base 24 Laser oscillator 26X, 26Y Galvanometer mirror 28 fθ lens 30 XY stage 32 Reduction optical unit 34 Robot arm (actuator)
38 Reflecting optical system 40 Neutralizing filter 42 Reduction lens optical system 44, 46, 48, 50 Folding mirror 56 Optical path length adjustment unit

Claims (13)

A laser marking device for marking a desired pattern by irradiating a workpiece with a laser beam by a scanning method,
A stage for supporting a work piece at a predetermined position;
A laser oscillation unit that oscillates and outputs a laser beam for marking;
A scan mirror that reflects the laser light from the laser oscillating toward the workpiece on the stage, and a light condensing that condenses the laser light from the scan mirror at a predetermined focal length. A laser scanning unit that optically scans an irradiation position of the laser beam on the workpiece by rotating and displacing the scan mirror;
Provided movably between a first position that interrupts the laser beam path between the laser scanning unit and the stage while maintaining a constant distance between the laser scanning unit and the stage, and a second position that retracts from the laser beam path reducing possess an optical system, which is,
When the reduction optical system is arranged at the second position, the laser beam emitted from the laser scanning unit is directly condensed on the workpiece, and the desired pattern is not reduced. And
When the reduction optical system is disposed at the first position, the laser light emitted from the laser scanning unit is once focused on the workpiece after being focused in the reduction optical system. Then, a desired pattern is marked by being reduced at a desired reduction rate.
Laser marking device. A unit main body for supporting or housing the reduction optical system;
A moving mechanism for moving the unit main body to move the reduction optical system between the first position and the second position;
The laser marking device according to claim 1, further comprising a control system for controlling the operation of the moving mechanism . A laser marking device for marking a desired pattern by irradiating a workpiece with a laser beam by a scanning method,
A stage for supporting a work piece at a predetermined position;
A laser oscillation unit that oscillates and outputs a laser beam for marking;
A scan mirror that reflects the laser light from the laser oscillating toward the workpiece on the stage, and a light condensing that condenses the laser light from the scan mirror at a predetermined focal length. A laser scanning unit that optically scans an irradiation position of the laser beam on the workpiece by rotating and displacing the scan mirror;
A reduction optical system disposed between the laser scanning unit and the stage so as to be interposed only in a partial region of the maximum marking range that can be scanned by the laser scanning unit,
In the area of the maximum marking range where the reduction optical system is not interposed, the laser beam emitted from the laser scanning unit is directly focused on the workpiece, and a desired pattern is marked without being reduced. ,
In the region where the reduction optical system is interposed in the maximum marking range, the laser beam emitted from the laser scanning unit is once focused on the workpiece after being focused in the reduction optical system. The desired pattern is marked by being reduced at a desired reduction rate.
Laser marking device. The reduction optical system is
A plurality of folding mirrors arranged in a predetermined relative positional relationship, wherein the laser light from the laser scanning unit is sequentially folded by the plurality of folding mirrors, and a laser beam path length between the scanning unit and the stage is set to a predetermined value; A reflective optical system that extends by a distance;
The laser according to claim 1 , further comprising: a reduction lens optical system that has a constant reduction magnification and that reduces and condenses the laser light from the reflection optical system on the workpiece. Marking device. The reflective optical system includes first, second, third and fourth folding mirrors;
The first folding mirror reflects the laser light that travels straight in a substantially vertical direction from the laser scanning unit toward the second folding mirror in a substantially horizontal direction;
The second folding mirror reflects the laser beam traveling straight in a substantially horizontal direction from the first folding mirror in a substantially vertical direction toward the third folding mirror;
The third folding mirror reflects the laser light traveling in a substantially vertical direction from the second folding mirror in a substantially horizontal direction toward the fourth folding mirror;
The fourth folding mirror reflects the laser light traveling straight in a substantially horizontal direction from the third folding mirror in a substantially vertical direction toward the reduction lens optical system ;
The laser marking device according to claim 4. The laser marking device according to claim 1 , wherein the reduction optical system includes an optical path length adjusting unit for adjusting an optical path length of the laser light. The optical path length adjustment unit has a mirror horizontal position adjusting section for adjusting portion or the position of the folding mirror in a total of horizontal, laser marking device according to claim 6. The reduction optical system has a neutral density filter for attenuating the light intensity of the laser beam, the laser marking device according to any one of claims 1 to 7. The laser marking device according to any one of claims 4 to 8 , wherein the reduction lens optical system includes a microscope lens. The laser marking device according to any one of claims 1 to 9 , wherein the stage includes an XY stage mechanism for moving and positioning the workpiece in an arbitrary direction within a horizontal plane. The laser marking device according to any one of claims 1 to 10 , wherein a wavelength of the laser light is 350 nm to 550 nm. The laser marking device according to claim 1 , wherein the scan mirror is a galvanometer mirror. The laser marking device according to claim 1 , wherein the condensing lens of the scanning unit is an fθ lens.

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