JP4279369B2 - Semiconductor device processing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a processing method using a focused ion beam of a semiconductor device or the like for the purpose of repairing or characterization of a semiconductor device such as an IC or LSI, and failure analysis. In addition, the present invention relates to a processing method suitable for processing in a short time.
[0002]
[Prior art]
In a semiconductor device whose density is increasing due to miniaturization / multilayering of wiring and the like, if any wiring can be cut or connected and defect analysis and partial repair can be performed quickly, the development period can be greatly shortened.
[0003]
As a technology that makes this possible, there is a processing and film forming method using a focused ion beam (hereinafter abbreviated as FIB) described in pages 27-32 of the September 1987 issue of “Monthly Semiconductor World”. Are known.
[0004]
FIB processing is an application of sputtering by FIB.
[0005]
First, an ion beam extracted from an ion source such as Ga is focused and irradiated to a spot diameter of 0.5 μm or less on a semiconductor device placed in a vacuum by an electrostatic lens, and two-dimensionally scanned by a deflector. Thereby, secondary electrons and secondary ions are generated from the surface of the semiconductor device. This secondary electron or secondary ion is detected by a detector, and a scanning ion microscope image (hereinafter referred to as SIM (= Scanning Ion) is displayed on the CRT with a luminance modulation signal in accordance with the detection intensity in synchronization with the scanning in the same manner as in the scanning electron microscope. Microscope) image).
[0006]
Therefore, this SIM image reflects the surface shape of the semiconductor device as in the scanning electron microscope. For example, in the semiconductor device 100 having the structure shown in FIG. 6, the uneven shape of the uppermost protective film 105 is the monitor of the SIM image. It is displayed on the screen 43. At this time, information on the first-layer Al wiring 103a under the planarized interlayer insulating film 104a cannot be obtained, but the second-layer and third-layer Al wirings 103b and 103c are interlayer insulating films thereon. Since 104b and the protective film 105 are not flattened, unevenness corresponding to the presence or absence of the Al wirings 103b and 103c is reflected in the protective film 105. The resolution depends on the spot diameter of the ion beam to be irradiated. The smaller the spot diameter, the finer the surface state can be expressed.
[0007]
The operator first searches for a specific pattern such as an alignment mark in the semiconductor device using the SIM image. Next, the stage on which the semiconductor device is mounted is moved from the pattern to the processing position based on the processing coordinate data, and the processing position is set while observing the SIM image again.
[0008]
After the processing position is set, a processing dimension (= FIB scanning area) is set, and FIB is irradiated for a predetermined time or while watching the change of the secondary electrons or secondary ions. By this FIB irradiation, the protective film, the interlayer insulating film and the Al wiring constituting the semiconductor device are sequentially removed from the surface by sputtering, and the connection window is opened and the wiring is cut.
[0009]
On the other hand, film deposition is an application of chemical vapor deposition (hereinafter abbreviated as CVD), which uses FIB as an energy source for CVD gas decomposition, and is also called FIB-CVD. In this method, after alignment by the above method, a film formation region (= FIB scanning region) is set. Next, CVD gas is blown onto the semiconductor device from a nozzle to form a CVD gas atmosphere, and FIB is irradiated and scanned for a predetermined time. Thereby, the CVD gas adsorbed on the surface of the semiconductor device is decomposed to form a film of metal or the like.
[0010]
In the above-mentioned conventional example, the above-mentioned FIB processing and FIB-CVD are applied to the electrical characteristic evaluation of an ECL gate array having a two-layer wiring structure and 1M DRAM, and the usefulness thereof is described.
[0011]
[Problems to be solved by the invention]
However, the wiring structure of recent semiconductor devices is much finer and more multilayered than the conventional semiconductor device. In order to realize this complicated wiring structure, each interlayer insulating film is planarized using a CMP (= Chemical & Mechanical Polishing) technique or the like.
[0012]
FIG. 7a) shows an example, and the interlayer insulating films 104a, 104b, 104c on the Al wirings 103a, 103b, 103c from the first layer to the third layer are flattened. As shown in FIG. 7B), the SIM image of the semiconductor device 100 having such a structure can be obtained only for the uppermost Al wiring 103d, so that the lower Al wirings 103a, 103b, and 103c are observed while viewing the SIM image. On the other hand, it is difficult to perform highly accurate processing positioning. The reason for this is that when the semiconductor device 100 is moved and positioned based on the coordinate data from the alignment mark or the like without looking at the SIM image, a positional shift occurs due to the inclination of the semiconductor device 100, variations in stage accuracy, etc. Because. If processing such as wiring cutting is performed in this state, problems such as processing of adjacent wiring along with the target wiring may occur.
[0013]
An object of the present invention is to solve such problems and to provide an effective processing method according to the structure of the target portion for a processing target of a semiconductor device in which SIM image observation is difficult or impossible. .
[0014]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, since the protective film and the interlayer insulating film of the semiconductor device are optically transparent, a film that can be observed with light and charged particles is formed at the processing position of the semiconductor device or in the vicinity thereof After forming a mark by removing a part of the film, the relative distance between the mark and the processing position is measured using an optical microscope having a length measuring function, and the mark and the measurement result The FIB processing is performed after specifying the processing position with reference to FIG.
[0015]
Here, the vicinity of the processing position refers to the area within the SIM image observation region at the final stage during FIB processing positioning.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an embodiment of an FIB processing apparatus according to the present invention.
[0017]
The processing apparatus according to this embodiment includes three chambers, a load lock chamber 10, a processing chamber 20, and an FIB optical chamber 30, and the load lock chamber 10 and the processing chamber 20 are isolated by a gate valve 11, and the processing chamber 20 and the FIB optical chamber are separated. 30 is divided by a partition plate 31 having an opening for FIB passage. The vibration isolation table 69 is for preventing vibration from the floor, and at least the load lock chamber 10, the processing chamber 20, the FIB optical chamber 30 and the optical system 50 are placed thereon.
[0018]
The load lock chamber 10 includes a door 13 for taking in and out the semiconductor device 100 placed and fixed on the holder 12, and a transport mechanism 14 for transporting the semiconductor device 100 together with the holder 12 into the processing chamber 20. I have. In addition, a vacuum gauge 15a for detecting the degree of vacuum in the load lock chamber 10, a vacuum pump 17 via an exhaust valve 16a, and a leak gas supply means 19 via a leak valve 18 are connected by piping.
[0019]
The processing chamber 20 includes a stage 21 that can move in each of the X, Y, Z, and θ directions, a secondary particle detector 22 for detecting secondary charged particles generated by ion irradiation on the upper surface, and an etching gas. And nozzles 23 for supplying CVD gas and their supply means 24, an objective lens 25 for observing the semiconductor device 100, a drive mechanism 26 for switching the objective lens 25, and a window 27 for introducing laser light It has. Further, a vacuum gauge 15b and an exhaust valve 16b for detecting the degree of vacuum in the processing chamber 20 are connected to the lower surface by piping.
[0020]
The reason why the objective lens 25 is provided in the processing chamber 20 is that a high numerical aperture lens with a small working distance can be used to enable observation with high magnification and high resolution, and the relative relationship between a mark and a processing position described later. This is to increase the accuracy of distance measurement. Further, by providing a plurality of objective lenses 25, an appropriate object can be selected and used according to the form (wafer, chip, package product) of the semiconductor device 100 to be processed. For example, when the semiconductor device 100 to be processed is a wafer or a chip, a high numerical aperture objective lens 25 having a small working distance is used, and in the case of a package product, a low numerical aperture objective lens 25 having a relatively large working distance is used. Is used. In the latter case, the resolution is lower than in the former case, but it can be dealt with by image processing of the image processing device 59 (electrically increasing the observation magnification and dividing and interpolating optically obtained pixels).
[0021]
The FIB optical chamber 30 is connected to the side by a vacuum pump 32 for exhausting the inside of the chamber 30, and includes an ion source 33, an extraction electrode 34, a focusing lens 35, a blanking electrode 36, an aperture 37, and a deflector electrode 38 inside. The objective lens 39 is provided. The ion beam 40 extracted from the ion source 33 by the extraction electrode 34 is focused by the focusing lens 35, passes through the aperture 37 for limiting the current and the focusing diameter, and the semiconductor device 100 with a fine spot diameter by the objective lens 39. Irradiated on top. At this time, by controlling the voltage applied to the blanking electrode 36 and the deflector electrode 38 with a controller (not shown), the ion beam 40 irradiation can be turned on and off, and the ion beam 40 can be scanned on the semiconductor device 100. It becomes. The secondary charged particles 41 from the semiconductor device 100 generated by the ion beam 40 irradiation are detected by the secondary particle detector 22.
[0022]
The detector 22 has a monitor 43 for displaying an image processed by the image processing device 42 via an image processing device 42 for performing various image processing in synchronization with the scanning of the ion beam 40. It is connected. Note that the optical axis of the ion beam 40 and the optical axis of the objective lens 25 are located at a predetermined distance, and by giving the value to the movement amount of the stage 21, it is possible to observe the substantially same position.
[0023]
Further, an optical system 50 for performing optical observation is provided immediately above the objective lens 25 in the processing chamber 20. The optical system 50 includes a laser oscillator 51 serving as an observation light source, a total reflection mirror 53 that guides laser light 52 emitted from the oscillator 51, an aperture 54 that shapes the laser light 52, and a laser light 52 that is planar in the X and Y directions. Scanning means 55, half mirror 56, pinhole 57, photodetector 58 that detects the amount of laser light 52 ′ that has passed through the pinhole 57, and detection signal from the detector 58 for scanning the laser light 52 An image processing device 59 for performing various image processing in synchronization and a monitor 60 for displaying an image processed by the image processing device 59 are configured.
[0024]
The aperture 54 and the pinhole 57 are placed at the image forming position of the objective lens 25. The laser beam 52 formed by the aperture 54 is projected onto the semiconductor device 100, and the image of the semiconductor device 100 is pinholed by the objective lens 25. The image is formed at position 57. The scanning means 55 constitutes a galvanometer by two total reflection mirrors and a driving mechanism thereof, and rotates the two total reflection mirrors at desired angles, respectively, so that the laser beam 52 is directed onto the semiconductor device 100 in the X and Y directions. Scanning. In place of the galvanometer, an acousto-optic deflector or an electro-optic deflector may be used in combination. The image processing device 59 has a function of displaying two sets of cross cursors on the monitor 60 screen, and from the number of pixels of the monitor 60 screen between the two sets of cross cursors and the magnification of the objective lens 25 used for observation. It has a function to obtain the distance between both cross cursors.
[0025]
In the optical system 50, the laser light 52 emitted from the laser oscillator 51 is incident on the aperture 54 by the total reflection mirror 53. The laser beam 52 is shaped by the aperture 54 and reaches the scanning means 55. Here, the laser beam 52 is scanned with respect to the XY plane, enters the objective lens 25, and passes through the spot size obtained by multiplying the aperture size of the aperture 54 by the reciprocal (1 / M) of the magnification M of the objective lens 25. Projected and scanned. Then, the reflected light 52 ′ from each pattern such as the wiring in the semiconductor device 100 passes through the objective lens 25 and the half mirror 56 and reaches the pinhole 57.
[0026]
As described above, since the pinhole 57 is placed at the image forming position of the objective lens 25, the reflected light 52 'from the pattern located on the focal plane of the objective lens 25 passes through the pinhole 57 most efficiently. To the light detector 58. Then, by setting a threshold value of the detected light quantity in the image processing device 59, only the pattern positioned on the focal plane of the objective lens 25 can be displayed on the monitor 60 and stored in the image processing device 59. Images are captured while moving the stage 21 in the Z direction, and by superimposing them, the lower layer wiring to the upper layer wiring in the semiconductor device 100 can be collectively displayed on the screen of the monitor 60.
[0027]
Next, the FIB processing procedure using the above embodiment will be described. Here, description will be made on the assumption that the wiring in the semiconductor device 100 shown in FIG.
[0028]
1) Introduction of semiconductor device First, layout data of the semiconductor device 100 to be processed and information such as a processing position, processing depth and material are input and stored in a controller (not shown) via a network or a magnetic medium.
[0029]
The exhaust valve 16a is closed, the leak valve 18 is opened, and an inert gas such as nitrogen or argon or a leak gas such as dry air is introduced into the load lock chamber 10 from the leak gas supply means 19. When the inside of the load lock chamber 10 reaches substantially atmospheric pressure, the valve 18 is closed to stop the supply of leak gas. The semiconductor device 100 having the door 13 opened and fixed to the holder 12 is placed on the transport mechanism 14 together with the holder 12, and the door 13 is closed. The valve 16b is closed and the valve 16a is opened to evacuate the load lock chamber 10 until a predetermined pressure (for example, 10-4 Pa) is reached. When the predetermined pressure is reached, the valve 16b and the gate valve 11 are opened.
[0030]
After the stage 21 is moved to the delivery position of the holder 12, the transport mechanism 14 is driven to move the holder 12 from the mechanism 14 to the stage 21. The stage 21 is moved to position the semiconductor device 100 directly below the objective lens 25.
[0031]
2) Correction of tilt of semiconductor device As shown in FIG. 2B, after the cross cursor 70 is displayed on the screen of the monitor 60, the stage 21 is moved while observing various patterns of the semiconductor device 100. The intersection point and the first alignment mark 2 used when manufacturing the semiconductor device 100 are matched. After storing the coordinates of the stage 25 where both coincide, the stage 25 is moved based on the layout data, and the intersection of the second alignment mark and the cross cursor 70 is made coincident. The stage coordinates here are compared with the stage coordinates in the first alignment mark 2 to determine the inclination θ1 of the semiconductor device 100 in the XY plane. Based on the obtained result, the tilt of the semiconductor device 100 is corrected by rotating the stage 25 in the reverse direction by θ1.
[0032]
Although the alignment mark 2 is used to correct the tilt of the semiconductor device 100, a pattern such as a wiring in the semiconductor device 100 may be used. Further, coordinate conversion may be performed according to the inclination θ1, and the stage 21 may be performed based on the converted coordinates without rotating the stage 21.
[0033]
3) Formation of mark base film After the above operation, the stage 21 is moved by a predetermined amount so that the semiconductor device 100 is positioned in the observation region of the SIM image, and the SIM image of the semiconductor device 100 and the cross cursor 80 are displayed on the monitor 43 screen. indicate. The stage 21 is moved while appropriately changing the observation magnification to search for the alignment mark 2. Then, the observation magnification is sequentially increased and the stage 21 is moved so that the center of the alignment mark 2 coincides with the intersection of the cross cursor 80 as in the case of the tilt correction of the semiconductor device in the above step 2). After the operation, the stage 21 is moved based on the coordinate data of the processing position 1. As a result, the processing position 1 is located somewhere in the observation area (in the display screen of the monitor 43) by the SIM image. The coordinates of the stage 21 at this time are stored in the controller, and then the observation magnification based on the SIM image is set to an observation area suitable for final alignment when the processing position 1 is FIB processed (for example, □ 20 to 100 μm). The magnification is such that
[0034]
Next, as shown in FIG. 2c), a box 81 for setting the scanning region of the ion beam 40 at the time of FIB processing is displayed on the monitor 43 screen, and X for forming a mark underlayer by FIB-CVD. The scanning area in the direction and the Y direction is input to the controller. The scanning area may be anywhere as long as it exists within the screen of the monitor 43.
[0035]
After setting the scanning region, the valve of the CVD gas supply means 24a is opened, and the ion beam 40 is irradiated under predetermined conditions while blowing the CVD gas from the nozzle 23a. After the irradiation for a predetermined time, the CVD gas supply means 24a is closed to stop the CVD gas supply. As a result, as shown in FIG. 2c), the mark base film 3 is formed in the scanning region.
[0036]
As the CVD gas used here, a gas that decomposes by ion beam irradiation to precipitate a metal is suitable. For example, a carbonyl compound that precipitates W, Mo, Cr, etc. (W (CO) 6, Mo (CO) 6 , Cr (CO) 6, etc.), or organometallic compounds that deposit Au, Cu, Pt, Al, etc. The film thickness necessary for the mark base film 3 varies depending on the material of the formed film and the number of observations of the SIM image at the time of alignment, but may be 1 μm or less.
[0037]
An excess film 3 ′ deposited at the bottom of the energy distribution of the ion beam 40 is also formed around the base film 3. In observation with a SIM image or a laser microscope, the boundary between the surplus film 3 ′ and the base film 3 is unclear and cannot be used as a mark in this state.
[0038]
4) Mark formation A box 81 for setting the scanning area at the time of FIB processing is displayed on the monitor 43 screen, and as shown in FIG. 3a), the processing area of the mark base film 3 formed in the above process is set. To do. After the setting, the base film 3 is partially removed by irradiation / scanning with the ion beam 40 under predetermined conditions. In this removal processing, the base film 3 is sputtered and removed by the ion beam 40, and the etching gas supply means 24b is opened and the etching gas for the metal film (for example, halogen gas such as chlorine, bromine or the like alone) from the nozzle 23b. Alternatively, there is a method of irradiating the ion beam 40 while spraying the compound) and reacting the metal film with the etching gas with the energy of the ion beam 40 to remove it.
[0039]
By any one of these methods, the base film 3 is partially removed to form the mark 4. Note that the processing depth in the mark formation may exceed the film thickness of the base film 3 and be processed to the middle of the protective film.
[0040]
5) Measuring the relative distance from the mark to the machining position
After forming the mark by FIB processing, the stage 21 is moved, and the mark 4 and the processing position 1 are displayed on the monitor 60 screen. As shown in FIG. 3 b), the first cross cursor 70 is aligned with the mark 4 and the second cross cursor 70 ′ is aligned with the processing position 1. Due to the function of the image processing device 59, distances (δx, δy) between the cross cursors 70 and 70 ′ in the X direction and the Y direction are obtained.
[0041]
6) FIB processing The stage 21 is moved to the coordinate position stored in the controller in the above step 3), and the SIM image of the semiconductor device 100 and the cross cursor 80 are displayed on the monitor 43 screen. On the screen of the monitor 43, as shown in FIG. 3c), the base film 3 and the mark 4 are displayed. Similarly to the case where the relative distance from the mark 4 to the processing position 1 is measured, the cross cursor 80 is aligned with the mark 4 and the second cross cursor 80 ′ is placed at a position away from the cross cursor 80 by (δx, δy). indicate. Since the intersection point of the second cross cursor 80 'indicates the processing position 1, a box 81 for setting a scanning area at the time of FIB processing around the intersection point is displayed on the monitor 43 screen. A machining area is set based on machining data previously input to the controller. After the setting, the protective film, the interlayer film, and the wiring are sequentially removed by irradiating and scanning the ion beam 40.
[0042]
Also in this removal processing, similarly to the mark formation on the base film 3, each layer is sputtered and removed by the ion beam 40, and the ion beam 40 is irradiated while switching the etching gas and is insulated by the energy of the ion beam 40. There is a method of removing a film or wiring by reacting with an etching gas. As the etching gas for the insulating film, fluorine or a fluorine compound such as XeF2, NF3, CF4, etc. is suitable, and as the etching gas for wiring, chlorine, bromine, etc. used for processing the base film 3 are used. A halogen gas alone or a compound thereof is suitable.
[0043]
7) Removal of semiconductor device
After the FIB processing is completed, the stage 21 is moved to the position where the holder 12 is transferred to the load lock chamber 10. After confirming that the load lock chamber 10 is in a high vacuum state, the gate valve 11 is opened and the transfer mechanism 14 is driven to transfer the semiconductor device 100 together with the holder 12 into the load lock chamber 10.
[0044]
Next, the gate valve 11 is closed, the valve 16 a is closed, the leak valve 18 is opened, and the leak gas is introduced into the load lock chamber 10. When the inside of the load lock chamber 10 reaches substantially atmospheric pressure, the leak valve 18 is closed, the door 13 is opened, and the semiconductor device 100 is taken out together with the holder 12. Then, the door 13 and the valve 16b are closed, the valve 16a is opened, and the load lock chamber 10 is exhausted. When the predetermined pressure is reached, the valve 16b is opened and the process ends.
[0045]
The above is an example in which the semiconductor device is formed from mark formation to wiring cutting using the FIB processing apparatus of the present invention.
[0046]
The present invention is not limited to the above embodiment. For example, in the FIB processing apparatus of FIG. 1, the laser oscillator 51 is replaced with a general light source for an optical microscope such as a halogen lamp, and white light is used as observation light. The distance between the mark 4 and the processing position 1 may be measured. Further, an FIB processing apparatus having a CVD means and an optical microscope may be provided separately.
[0047]
Further, the tilt correction of the semiconductor device 100 in the step 2) may be performed using the FIB optical system and observing the alignment mark 2 with a SIM image.
[0048]
Further, the shape and the formation location of the mark 4 are not limited to the above embodiment, and the mark 4 may be formed by removing the mark base film 3 into a cross shape as shown in FIG. 4A, for example. Alternatively, as shown in FIG. 4b), after forming the mark base film 3 by FIB-CVD on the entire SIM image observation area at the time of final processing alignment, the processing position within the observation area at the time of final processing alignment The mark 4 may be formed by widely removing the base film 3 by FIB processing so that 1 is included. Then, as shown in FIG. 4c), distances (δx, δy) from the two sides of the widely formed mark 4 to the processing position 1 are measured.
[0049]
At this time, the area for removing the mark undercoat film 3 (= dimension size of the mark 4) is such that, in the distance measurement from the mark 4 to the processing position 1 in the above step 5), the observation light is applied to the processing position 1 and its periphery. The size is sufficiently irradiated (for example, □ 20 μm).
[0050]
In this removal process, as described above, the base film 3 is sputtered and removed by the ion beam 40, and the ion beam 40 is irradiated while the etching gas is blown to react the metal film and the etching gas with the energy of the ion beam 40. There is a method to remove. However, when the base film 3 is sputtered away using metal Ga for the ion source 33, Ga is implanted into the exposed protective film 105, the transmittance of the protective film 105 is lowered, and the processing position 1 is optically changed. Since it becomes difficult to see, it is better to process while blowing etching gas. The etching gas is not limited to the etching gas for the metal film (for example, a halogen gas such as chlorine or bromine, or a compound thereof), but fluorine or XeF2, NF3, CF4, etc. It may be a fluorine compound. Then, the protective film 105 may be processed halfway beyond the thickness of the base film 3.
[0051]
Furthermore, a plurality of base films 3 and marks 4 may be formed in the observation region at the time of final alignment when the processing position 1 is subjected to FIB processing. Then, as shown in FIG. 5a), when the relative distance from the mark 4 to the processing position 1 is measured with the laser microscope, the intersection of the two cross cursors 70 and 70 'is the center of the marks 4 and 4', respectively. The distance x1 between the marks 4 and 4 'is also measured in accordance with the same, and the intersection of the two cross cursors 80 and 80' is also aligned with the centers of the marks 4 and 4 'in the SIM image observation. The distance x2 between both marks 4 and 4 'is measured. By setting the setting position of the scanning area setting box 81 at the time of FIB processing to (δx × x2 / x1, δy × x2 / x1), setting errors due to differences in observation systems can be eliminated. Here, the two marks 4 and 4 ′ are formed in the X direction, and the distance (δx, δy) from the mark 4 to the processing position 1 is corrected based on the two marks 4 and 4 ′, but as shown in FIG. The distances x1 and y1 in the X direction and the Y direction may be obtained by forming them at positions, and may be corrected as (δx × x2 / x1, δy × y2 / y1).
[0052]
【The invention's effect】
As described above, according to the present invention, after forming a mark in the SIM image observation area at the final positioning of FIB processing, the mark and the processing position are displayed on the same screen by an optical microscope and measured on the screen, In order to set the processing area at the position based on the mark display and the above measurement results on the same screen as the SIM image observation magnification at the time of final positioning, the secondary ion image or secondary image of FIB from the processing area by flattening processing etc. Even in a semiconductor device in which information on a processing position based on an electronic image cannot be obtained, the processing position can be easily and accurately specified.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view showing an example of an FIB processing apparatus according to the present invention.
FIGS. 2A and 2B are diagrams illustrating a process of processing a semiconductor device according to the present invention.
FIG. 3 is a plan view of the semiconductor device in each processing step according to the present invention.
FIG. 4 is a plan view of a semiconductor device showing an example of a mark in the present invention.
FIG. 5 is a plan view of a semiconductor device showing an example of a mark in the present invention.
FIG. 6 is a plan view and a cross-sectional view showing a schematic configuration of a conventional semiconductor device.
7A and 7B are a plan view and a cross-sectional view showing a schematic configuration of a semiconductor device to be processed in the present invention.
[Explanation of symbols]
1 --- Processing position, 2 --- Alignment mark, 3 --- Undercoat film for mark formation, 4 --- Mark, 10 --- Load lock chamber, 14 --- Transfer mechanism, 20 --- Processing chamber, 21 --- Stage, 22 --- Secondary particle detector, 23 --- Nozzle, 24 --- Gas supply means, 25 --- Objective lens, 30 --- FIB optics chamber, 33-- -Ion source, 34 --- Extraction electrode, 35 --- Focusing lens, 39 --- Objective lens, 40 --- Ion beam, 41 --- Secondary particles, 42 --- Image processing device, 43 --- Monitor, 50 --- Optical system, 51 --- Laser oscillator, 52 --- Laser beam, 58 --- Photo detector, 59 --- Image processing device, 60 --- Monitor, 100- --Semiconductor device, 101 --- Substrate, 102 --- Oxide film, 103 --- Al wiring, 104 --- Interlayer insulating film, 105 --- Protective film.

Claims (5)

A step of forming a mark that can be observed using light and charged particles at or near the processing position of a semiconductor device, and a relative distance between the mark and the processing position using an optical microscope having a length measurement function And a step of performing focused ion beam processing after specifying the processing position with reference to the measurement result and the mark, and performing each of the above steps continuously in the same chamber without breaking the vacuum. A method for processing a semiconductor device. The step of forming a mark that can be observed using light and charged particles in the observation region when the processing position of the semiconductor device is specified from the charged particle image, and the relative distance between the mark and the processing position is measured. A step of performing measurement using an optical microscope having a long function, and a step of performing focused ion beam processing after specifying the processing position with reference to the measurement result and the mark, and performing each of the steps in the same chamber. A method for processing a semiconductor device, which is performed continuously without breaking a vacuum.   After positioning the processing position in the observation area at the time of alignment in focused ion beam processing, a film capable of observation using light and charged particles is provided in the observation area, and then the film is removed and marked And measuring the relative distance between the mark and the processing position using an optical microscope having a length measuring function, specifying the processing position with reference to the measurement result and the mark, and then focusing ion beam A processing method of a semiconductor device, characterized by performing processing.   Length measurement function after forming a film that can be observed using light and charged particles in the region including the processing position by the focused ion beam, and removing the film at least in the region including the processing position. Measuring the relative distance between the mark and the position to be processed using an optical microscope, and performing the focused ion beam processing after specifying the position to be processed with reference to the measurement result and the mark. A method for processing a semiconductor device.   After applying a film that allows observation using light and charged particles to the region including the processing position by the focused ion beam, selectively irradiate at least the region including the processing position with the focused ion beam in an etching gas atmosphere. After scanning to form a mark, the relative distance between the mark and the processing position is measured using an optical microscope having a length measurement function, and the processing position is identified with reference to the measurement result and the mark. A method of processing a semiconductor device, characterized by performing focused ion beam processing.

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