JP4180325B2 - Laser marking device and laser marking method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a laser marking apparatus and a laser marking method for marking a pattern generated on a mask, for example, on a chip of a silicon wafer.
[0002]
[Prior art]
As a conventional liquid crystal mask type laser marking device, for example, an IC package which irradiates a laser beam and prints a product name, a lot number or the like is known. In this conventional liquid crystal mask type laser marking device, printing is performed by scanning a liquid crystal mask displaying an IC print pattern with a laser beam and forming an image on the print surface of the IC. When the printing of one IC is completed, the table on which the IC is placed moves, the IC to be printed next is set at the printing position, and printing is performed sequentially.
[0003]
[Problems to be solved by the invention]
In recent years, a semiconductor device of a type called a wafer level CSP has been increasing, and in the manufacturing process of this semiconductor device, there is a case where individual chips are marked in a pre-process for individualization. In this case, in the conventional liquid crystal mask type laser marking apparatus, it is necessary to repeatedly move the silicon wafer by the chip size every time one chip is printed. Takes a long time to print.
[0004]
An object of the present invention is to provide a laser marking apparatus and a laser marking method capable of marking a pattern in a short time.
[0005]
[Means for Solving the Problems]
(1) In the laser marking method according to the first aspect of the present invention, at least two or more common laser marking methods are provided in a region corresponding to a small region on a wafer partitioned so as to include a plurality of chips on the mask. A pattern is generated, the pattern on the mask is scanned with a laser beam, and the pattern is marked collectively on a plurality of chips in a small area.
(2) The laser marking device according to the invention of claim 2 is based on a laser light source for irradiating a laser beam for marking a pattern on a chip, an input means for inputting pattern information, and information input by the input means. Then, a mask on which at least two or more common patterns are generated in an area having a size corresponding to a small area on the wafer partitioned to include a plurality of chips, and a pattern on the mask by laser light Scanning means for scanning and marking a pattern on a plurality of chips in a small region at once.
(3) According to a third aspect of the present invention, in the laser marking device according to the second aspect, each time a pattern is collectively marked on a stage on which a wafer is placed and a plurality of chips in a small area, And further comprising a control means for controlling the stage and the scanning means so as to mark all chips on the wafer by repeating the small area facing the mask and then scanning the mask with laser light. .
(4) According to a fourth aspect of the present invention, in the laser marking device according to the second or third aspect, the mask is a liquid crystal mask, and the wafer size and shape, the chip size and shape, and the pattern data input from the input means are used. And a liquid crystal control means for generating a pattern on the liquid crystal mask.
(5) The invention of claim 5 is the laser marking device of claim 4, wherein the liquid crystal control means receives the inspection result of whether the chip is defective or non-defective, and does not mark the pattern on the defective chip. The liquid crystal mask is driven as described above.
(6) The invention according to claim 6 is the laser marking device according to claim 4, wherein the liquid crystal control means receives the inspection result of whether the chip is defective or non-defective, and the defective chip has a pattern different from that of the non-defective product. The liquid crystal mask is driven so as to mark the mark.
(7) The invention according to claim 7 is the laser marking device according to claim 4, wherein the liquid crystal control means drives the liquid crystal mask so as not to generate a pattern in a portion where no chip exists in the small area. To do.
(8) The invention according to claim 8 is the laser marking device according to any one of claims 4 to 7, wherein a pattern different from the marking pattern performed on one small region of the liquid crystal mask is marked on the next small region. In this case, after the time required for changing the pattern of the liquid crystal mask, the irradiation of the marking laser to the next small area is resumed.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
――― First embodiment ―――
A first embodiment in which the present invention is applied to a liquid crystal mask type laser marking apparatus will be described with reference to FIGS. FIG. 1 is a view showing the structure of a liquid crystal mask type laser marking apparatus. The liquid crystal mask type laser marking device 1 includes a YAG laser oscillator 5 that generates laser light 2, a half-wave plate 10 that adjusts the polarization angle of the laser light 2, a galvano mirror 6 that scans the laser light 2, and a laser. A field lens 7 that irradiates the liquid crystal mask 8 with the light 2 with a predetermined light flux and a liquid crystal mask 8 that polarizes and emits the incident laser light 2 in accordance with the generated print pattern are provided. The liquid crystal mask type laser marking device 1 includes a polarizing beam splitter 11 that separates the laser light 2 according to the polarization angle, an absorber 12 that absorbs the laser light 2 separated by the polarizing beam splitter 11, and the polarizing beam splitter 11. An imaging lens 9 that focuses the laser beam 2 that has passed through the laser beam 2 on the printing surface of the silicon wafer 3 that is the object to be printed, a table 13 that moves the silicon wafer 3 on a plane perpendicular to the incident laser beam 2, and It has.
[0007]
The laser beam 2 output from the YAG laser oscillator 5 is linearly polarized light, and the polarization angle is converted by the half-wave plate 10 according to the characteristics of the liquid crystal used for the liquid crystal mask 8. The laser beam 2 whose polarization angle has been converted is scanned in the XY directions by the galvanometer mirror 6, passes through the field lens 7, and then scans the surface of the liquid crystal mask 8. When the laser beam 2 passes through the liquid crystal mask 8, it is converted into different polarization angles when it passes through the display portion of the liquid crystal mask 8 and when it passes through the non-display portion. The laser beam 2 that has passed through the display portion of the liquid crystal mask 8 is transmitted through the polarization beam splitter 11 and propagated to the imaging lens 9 and is imaged on the printing surface of the silicon wafer 3. The laser beam 2 transmitted through the non-display portion of the liquid crystal mask 8 is propagated to the absorber 12 by the polarization beam splitter 11 and absorbed. As a result, the pattern displayed on the liquid crystal mask 8 is transferred and printed on the printing surface of the silicon wafer 3 mounted on the table 13. The printing surface of the silicon wafer 3 is disposed so as to be an image forming position of the laser light 2 transmitted through the liquid crystal mask 8 by the image forming lens 9.
[0008]
In the printing with the laser beam 2 described above, even if the laser beam 2 is scanned with the galvanometer mirror 6, printing can be performed only in a limited range on the printing surface of the silicon wafer 3. Therefore, the silicon wafer 3 is moved in the X and Y directions by the table 13 and sequentially printed on the entire printing surface of the silicon wafer 3.
[0009]
In the liquid crystal mask type laser marking apparatus 1 according to the first embodiment, as shown in FIG. 2, a plurality of (n × m) chips are collectively printed by laser scanning without moving the table 13. That is, a small area on the wafer partitioned so as to include a plurality of chips is collectively printed. Therefore, in the liquid crystal mask type laser marking apparatus 1 of the first embodiment, as will be described in detail below, n × m identical print patterns are generated on the liquid crystal mask.
[0010]
FIG. 3 is a system block diagram relating to a printing control system of the liquid crystal mask type laser marking apparatus according to the first embodiment of the present invention. The printing control system of the liquid crystal mask type laser marking device 1 includes a main controller 16, a galvano controller 20, a liquid crystal controller 15, and a printing pattern creation device 14. A pattern to be printed on one chip 4 is created by the print pattern creation device 14. This pattern data is transferred to the liquid crystal controller 15 together with data representing the shapes of the silicon wafer 3 and the chip 4 described later. The liquid crystal controller 15 stores the transferred data and also transfers these data to the main controller 16.
[0011]
The main controller 16 creates print matrix data in a batch printable range according to the chip size from the transferred data. FIG. 4 shows an example of this, and represents 3 × 3 total 9 print matrix data created in the batch printable range. The created print matrix data is transferred to the liquid crystal controller 15. Based on the matrix data created by the main controller 16 and the print pattern data for one chip created by the print pattern creation device 14, the liquid crystal controller 15 prints the print data in the batch printable range as shown in FIG. Is generated in the liquid crystal mask 8. From the print pattern creation device 14, data of the scanning speed of the galvanometer mirror 6 calculated based on the print pattern data is transmitted to the galvano controller 20.
[0012]
The liquid crystal mask type laser marking device 1 scans the surface of the liquid crystal mask 8 on which the print data is displayed by the above-described print control with the laser beam 2 output from the YAG laser oscillator 5, thereby the same for a plurality of chips. Print the print pattern in a batch. When batch printing at one place is completed, the main controller 16 outputs a signal to the table 13, moves the table 13 to position the silicon wafer 3 in the next batch printing range, and then sends a signal to the YAG laser oscillator 5. Start batch printing. This process is sequentially repeated to print on the silicon wafer 3.
[0013]
As shown in FIG. 6, when the liquid crystal mask type laser marking apparatus 1 performs printing near the outer peripheral portion of the silicon wafer 3, the silicon wafer 3 may not exist at all in the batch printable range. Even if the silicon wafer 3 exists in the batch printable range, there is a case where there is no need for printing such as an end portion that cannot be processed into a chip. In such a case, as shown in FIG. 7, the matrix 17 that needs to be printed is displayed on the liquid crystal mask 8, and the matrix 18 that does not need to be printed is not displayed, so that printing is not performed on a portion that does not require printing. do it. A method for determining the execution position of batch printing on the silicon wafer 3 and the display / non-display of each matrix of batch printing will be described in detail below.
[0014]
In order to determine display / non-display of each matrix, the main controller 16 calculates the following data based on the data representing the size and shape of the silicon wafer 3 and the chip 4 transferred from the liquid crystal controller 15.
(1) Position of each chip 4 on the silicon wafer 3
(2) Batch printing location and batch printing sequence on silicon wafer 3
(3) From the data in (1) and (2), specify the print location and the unnecessary print location (chip map data) for batch printing.
[0015]
(1) Position of each chip 4 on the silicon wafer 3
As shown in FIG. 8, the size of the silicon wafer 3, the wafer edge size, the maximum number of chips in the vertical direction, the maximum number of chips in the horizontal direction, and the chip size (chip pitch) (hereinafter collectively referred to as wafer chip shape data and The position of each chip 4 on the symmetrical silicon wafer 3 is calculated by the main controller 16.
[0016]
(2) Batch printing location and batch printing sequence on silicon wafer 3
As described above, the main controller 16 calculates the array (print matrix data) of the chips in the batch printable range as shown in FIG. 4 from the chip size and the batch printable range as shown in FIG. From the printing matrix data and the position of each chip 4 on the silicon wafer 3 described above, as shown in FIG. 9, the batch printing location and order (hereinafter referred to as printing pattern data) of the silicon wafer 3 are calculated. In the example shown in FIG. 9, the batch printing is performed sequentially by moving the range of batch printing of a total of 3 × 3 chips 4 as indicated by arrows.
[0017]
(3) Identification of unnecessary printing areas for batch printing
The main controller 16 specifies a matrix to be printed and a matrix not to be printed from the above-described print matrix data and print pattern data. As shown in FIG. 10, “1” is assigned to a matrix in which each chip 4 exists, for example, a matrix located in C3L3 in FIG. 10, and “0” is assigned to a matrix in which no chip 4 exists, for example, a matrix located in C2L3 in FIG. Create a map with "" assigned. The map shown in FIG. 10 is called chip map data of the silicon wafer 3. Based on this chip map data, a matrix assigned “1” is a matrix displayed during batch printing, and a matrix assigned “0” is a non-displayed matrix during batch printing. To transmit data to the liquid crystal controller 15. As a result, as shown in FIG. 7, the matrix 17 that needs to be printed is displayed on the liquid crystal mask 8 and the matrix 18 that does not need to be printed is not displayed, so that printing is not performed on a portion that does not require printing. be able to.
[0018]
The operation of the liquid crystal mask type laser marking apparatus 1 according to the first embodiment of the present invention will be described with reference to the flowcharts shown in FIGS. FIG. 11 is a flowchart showing an operation performed by the main controller 16. When a power switch (not shown) of the liquid crystal mask type laser marking apparatus 1 is turned on, a program for performing the processing of FIG. 11 is started. In step S 1, the process waits until the wafer / chip shape data is received from the print pattern creation device 14. If it is determined that the wafer / chip shape data has been received, the process proceeds to step S3. Based on the wafer / chip shape data received in step S1, the above-described print matrix data, print pattern data, and chip map data are obtained. Calculate and proceed to step S5. In step S5, the matrix data calculated in step S3 and display / non-display data of each matrix based on the chip map data are transmitted to the liquid crystal controller 15, and the process proceeds to step S7. Step S7 is a waiting time for securing a time required for display switching when the display of the liquid crystal mask 8 is switched by data transmitted from the liquid crystal controller 15. After the elapse of the waiting time in step S7, the process proceeds to step S9, and the table 13 is moved to a predetermined position based on each data calculated in step S3. In step S11, the process waits until the positioning of the table 13 is completed.
[0019]
When the positioning of the table 13 is completed, the process proceeds to step S13, an oscillation start signal is transmitted to the YAG laser oscillator 5, and the process proceeds to step S15. In step S15, a scanning start signal for the galvano mirror 6 is transmitted to the galvano controller 20, and the process proceeds to step S17. In step S17, the process waits until a print end (scan end) signal is received from the galvano controller 20. If it is determined that the print end (scan end) signal has been received, the process proceeds to step S19, an oscillation stop signal is transmitted to the YAG laser oscillator 5, and the process proceeds to step S21.
[0020]
In step S21, it is determined whether or not printing of the entire range has been completed on one silicon wafer 3. If a negative determination is made in step S21, the process proceeds to step S23, and on the basis of the data calculated in step S3, display / non-display data of each matrix within the next batch printing range, that is, the matrix 17 that needs to be printed. Then, it is determined whether or not there is a change in the matrix 18 that does not require printing. If a negative determination is made in step S23, the process returns to step S9. If an affirmative determination is made in step S23, the process proceeds to step S25 to transmit display / non-display update data of each matrix to the liquid crystal controller 15, and the process returns to step S7.
[0021]
If an affirmative determination is made in step S21, the process proceeds to step S27, and it is determined whether or not all printing of the silicon wafer 3 to be printed mounted on the table 13 has been completed. If a negative determination is made in step S27, the process proceeds to step S29, the table 13 is moved to print the next silicon wafer 3, and the process returns to step S5. If an affirmative determination is made in step S27, the process proceeds to step S31, the print end data is transmitted to the liquid crystal controller 15, and the program is ended.
[0022]
In the above flowchart, step S9 may be executed simultaneously with the determination in step S23 after a negative determination is made in step S21.
[0023]
FIG. 12 is a flowchart showing an operation performed by the liquid crystal controller 15. When a power switch (not shown) of the liquid crystal mask type laser marking apparatus 1 is turned on, a program for performing the processing of FIG. 12 is started. In step S51, the process waits until a print pattern on each chip 4 and wafer chip shape data are received from the print pattern creation device 14. If it is determined in step S51 that the print pattern on each chip 4 and the wafer / chip shape data have been received, the process proceeds to step S53, and the wafer / chip shape data in the data received in step S51 is transferred to the main controller. 16 and proceeds to step S55. In step S55, the process waits until the matrix data calculated in step S3 in FIG. 11 and the display / non-display data of each matrix are transmitted from the main controller 16. If it is determined in step S55 that the data from the main controller 16 has been received, the process proceeds to step S57, and the matrix data received in step S55 and the data to be generated on the liquid crystal mask 8 from the display / non-display data of each matrix are obtained. Create and proceed to step S59. In step S59, the display data created in step S57 is generated on the liquid crystal mask 8, and the process proceeds to step S61.
[0024]
In step S61, it is determined whether display / non-display update data for each matrix transmitted from the main controller 16 in step S25 of FIG. 11 has been received. If a negative determination is made in step S61, the process proceeds to step S63, and it is determined whether the print end data transmitted from the main controller 16 is received in step S31 of FIG. If a negative determination is made in step S63, the process returns to step S59.
[0025]
If a positive determination is made in step S61, the process returns to step S57. If a positive determination is made in step S63, the program is terminated.
[0026]
Through the above-described processing, the liquid crystal mask type laser marking apparatus 1 repeatedly performs batch printing on a plurality of chips 4 corresponding to the positions of the chips 4 on the printing surface of the silicon wafer 3, so that all the chips 4 are printed. Can be printed.
[0027]
The liquid crystal mask type laser marking device according to the first embodiment of the present invention described above has the following operational effects.
(1) Print data in a batch printable range is generated on the liquid crystal mask 8 with the same print pattern of n × m pieces, and the surface of the liquid crystal mask 8 on which the print data is displayed is scanned with the laser beam 2 to obtain a plurality of print data. The same print pattern can be printed on the chip at a time. As a result, a plurality of chips can be printed at once without moving the silicon wafer 3, so that the tact time associated with the movement of the silicon wafer 3 can be greatly reduced.
(2) When there is no silicon wafer 3 in the batch printable range, or when there is no need for printing such as an edge that cannot be processed into a chip even if the silicon wafer 3 exists in the batch printable range, a liquid crystal mask In FIG. 8, the matrix 17 that needs to be printed is displayed, and the matrix 18 that does not need to be printed is not displayed, so that printing is not performed on a portion that does not require printing. Thereby, marking on a table surface or the like where the silicon wafer 3 does not exist can be prevented, and the table surface is not damaged.
[0028]
――― Second embodiment ―――
A second embodiment of a liquid crystal mask type laser marking device according to the present invention will be described with reference to FIGS. In the second embodiment, the chip 4 determined to be defective as a result of the non-defective product inspection of each chip 4 performed in the previous process of the laser marking process by the liquid crystal mask type laser marking device 1 of the present embodiment. Indicates that pattern printing is not performed. Since the second embodiment is the same as the first embodiment except for chip map data described later, detailed description thereof is omitted.
[0029]
  FIG. 13 shows a non-defective product data matrix created from the result of non-defective product inspection performed in the pre-process of the laser marking process. This data matrix is input to the main controller 16 by input means (not shown). In FIG. 13, a chip described as OK is described as a non-defective chip 41 and NG, and a chip surrounded by a thick frame is a defective chip 42. Chip map data shown in FIG. 14 is newly created from the input data of the non-defective product / defective product data matrix and the chip map data shown in FIG. That is, “0” is assigned to the chip (thick frame) on the chip map data shown in FIG. 10 corresponding to the defective product chip 42 from the input data of the non-defective product data matrix and new chip map data (FIG. 14). In the liquid crystal mask type laser marking apparatus 1 described in the first embodiment, if the new chip map data shown in FIG. 14 is used instead of the chip map data shown in FIG. The chip 4 determined to be defective is marked on the chip 4TheNot performed.
[0030]
The liquid crystal mask type laser marking device according to the second embodiment of the present invention described above has the following operational effects.
(1) As a result of the non-defective product inspection of each chip 4 performed in the previous process of the laser marking process, pattern printing is not performed on the chip 4 determined to be defective. As a result, it is possible to discriminate non-defective products of the chip 4 by image processing of laser marks or visual observation during chip mounting, and erroneous mounting of defective products can be prevented.
[0031]
You may make it perform NG marking to the chip | tip 4 judged to be defect. The good product / defective product data matrix shown in FIG. 13 is input to the main controller 16 by an input means (not shown). Chip map data shown in FIG. 15 is newly created from the input data of the non-defective product / defective product data matrix and the chip map data shown in FIG. In the chip map data of FIG. 15, “2” is assigned to the chip (thick frame) corresponding to the defective product chip 42 in the non-defective product data matrix. In the liquid crystal mask type laser marking apparatus 1 described in the first embodiment, the new chip map data shown in FIG. 15 is used instead of the chip map data shown in FIG. If the NG pattern data created / input by the print pattern creation device 14 is printed on the chip (thick frame) to which “” is assigned, the chip determined to be defective as a result of the non-defective product inspection. 4 is marked with NG.
[0032]
In each of the above-described embodiments, the pattern to be printed on the chip 4 and the shape data of the wafer chip are input from the print pattern creation device 14, but the present invention is not limited to this. Patterns to be printed on the chip 4 and wafer / chip shape data may be input to the liquid crystal mask type laser marking apparatus 1 from various manufacturing apparatuses in the pre-process of the laser marking process. In addition, a plurality of print patterns and wafer chip shape data registered in advance in the print pattern creation device 14 by signals sent to the liquid crystal mask type laser marking device 1 from various manufacturing devices in the pre-process of the laser marking step. Arbitrary data may be selected from the inside.
[0033]
In each of the above-described embodiments and modifications thereof, when there is an unnecessary portion for printing, the matrix of the unnecessary portion for printing is not displayed so that the laser beam 2 is not irradiated on the object to be printed. However, the present invention is not limited to this. By controlling the galvanometer mirror 6, the laser beam may be scanned only for the matrix that requires printing of the liquid crystal mask 8, and the laser beam may not be scanned for the matrix that does not require printing. In this case, the mask used is not limited to the liquid crystal mask. A fixed mask that cannot physically change the pattern may be used.
[0034]
In each of the above-described embodiments and modifications thereof, the print object is a silicon wafer, but is not limited to a silicon wafer. The present invention may also be applied to printing on mechanical parts that repeatedly print the same pattern. The mask used is not limited to a liquid crystal mask. In the case where all the positions can be marked with one scan with respect to the mask, there is no need to have a table for moving the print target in the XY directions. The above-described embodiments and modifications may be combined. Furthermore, the present invention is not limited to the above-described embodiment as long as the characteristic functions of the present invention are not impaired.
[0035]
In each of the above embodiments and modifications thereof, the laser light source corresponds to the YAG laser oscillator 5, the input means corresponds to the print pattern creation device 14, and the stage corresponds to the table 13. The scanning means includes a galvanometer mirror 6 and a galvano controller 20. Control means for controlling the stage and the scanning means corresponds to the main controller 16. The liquid crystal control means includes a main controller 16 and a liquid crystal controller 15.
[0036]
【The invention's effect】
As described above, according to the present invention, at least two or more common patterns can be generated on the mask, and the pattern on the mask can be scanned with a laser beam to mark a plurality of marked portions at once. The pattern can be marked in a short time.
[Brief description of the drawings]
FIG. 1 is a diagram showing the structure of a liquid crystal mask type laser marking device according to a first embodiment of the present invention.
2 shows a range in which batch printing is performed on a plurality of (n × m) chips by laser scanning without moving the silicon wafer 3 to be printed by the liquid crystal mask type laser marking apparatus 1 of FIG. 1 and the table 13. FIG. FIG.
3 is a system block diagram relating to a printing control system of the liquid crystal mask type laser marking device 1 of FIG. 1;
FIG. 4 is a diagram illustrating an example of print matrix data of a batch printable range created by the main controller 16;
FIG. 5 is a diagram showing print data in a collective printable range generated on the liquid crystal mask 8;
FIG. 6 is a diagram showing a print portion and a print unnecessary portion when printing near the outer peripheral portion of the silicon wafer 3;
7 is a view showing a display / non-display portion of the liquid crystal mask 8 in FIG. 6. FIG.
FIG. 8 is a diagram showing the size of the silicon wafer 3, the wafer edge size, the maximum number of chips in the vertical direction, the maximum number of chips in the horizontal direction, and the chip size (chip pitch).
FIG. 9 is a diagram showing the location and order of batch printing on a silicon wafer 3;
10 is a diagram showing chip map data of a silicon wafer 3. FIG.
11 is a flowchart showing an operation performed by the main controller 16. FIG.
12 is a flowchart showing an operation performed by the liquid crystal controller 15. FIG.
FIG. 13 is a view showing a non-defective product data matrix created from the result of non-defective product inspection of each chip 4 performed in the previous step of the laser marking process.
14 is a diagram showing chip map data newly created from the non-defective product / defective product data matrix data of FIG. 13 and the chip map data of FIG. 10;
15 is a diagram showing chip map data newly created from the non-defective product / defective product data matrix data of FIG. 13 and the chip map data of FIG. 10;
[Explanation of symbols]
1 Liquid crystal mask type laser marking device 2 Laser light
3 Silicon wafer 4 Chip
5 YAG laser oscillator 6 Galvano mirror
7 Field lens 8 LCD mask
9 Imaging lens 10 1/2 wavelength plate
11 Polarizing beam splitter 12 Absorber
13 Table 14 Print pattern creation device
15 LCD controller 16 Main controller
17 Matrix that needs to be printed 18 Matrix that does not need to be printed
20 Galvano controller 41 Non-defective chip
42 Defective chip

Claims (8)

Generating at least two or more common patterns in an area of a size corresponding to a small area on a wafer partitioned to include a plurality of chips on the mask;
A laser marking method, wherein a pattern on the mask is scanned with a laser beam, and the pattern is collectively marked on a plurality of chips in the small region. A laser light source that emits a laser beam for marking a pattern on the chip;
Input means for inputting information of the pattern;
A mask in which at least two or more common patterns are generated in an area having a size corresponding to a small area on a wafer partitioned so as to include a plurality of chips based on information input by the input means. When,
A laser marking apparatus, comprising: scanning means for scanning a pattern on the mask with the laser light and marking the pattern collectively on a plurality of chips in the small region. The laser marking device of claim 2,
A stage on which the wafer is placed;
Each time a plurality of chips in the small area are collectively marked with a pattern, the small area on the wafer to be marked next is opposed to the mask, and then the mask is scanned with laser light repeatedly. A laser marking apparatus, further comprising a control means for controlling the stage and the scanning means so as to mark all the chips above. The laser marking device according to claim 2 or 3,
The mask is a liquid crystal mask;
A laser marking apparatus, further comprising: a liquid crystal control unit that generates the pattern on the liquid crystal mask based on a wafer size and shape, a chip size and shape, and pattern data input from the input unit. The laser marking device according to claim 4,
The liquid crystal control means receives an inspection result of whether a chip is defective or non-defective, and drives the liquid crystal mask so as not to mark a pattern on the defective chip. The laser marking device according to claim 4,
The liquid crystal control means receives an inspection result of whether the chip is defective or non-defective, and drives the liquid crystal mask so as to mark a pattern different from the non-defective chip on the defective chip. apparatus. The laser marking device according to claim 4,
The laser marking device, wherein the liquid crystal control means drives the liquid crystal mask so that the pattern is not generated at a location where no chip exists in the small area. In the laser marking device according to any one of claims 4 to 7,
When marking the next small area with a pattern different from the marking pattern performed on one small area of the liquid crystal mask, after the time required for changing the pattern of the liquid crystal mask, Laser marking device characterized by restarting irradiation.

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