TW383264B - Multi-stage chemical-mechanical polishing method - Google Patents

Abstract

A kind of polishing mechanical device for semiconductor wafer which provides a precise alignment method for yellow light alignment machine. When the semiconductor wafer is allocated on the machine of chemical mechanical polishing device and proceeded chemical mechanical polishing, the steps include precisely changing the direction of polishing head or polishing platen of chemical mechanical polishing device in clockwise or counterclockwise direction and proceeding multi-stage polishing for the semiconductor wafer; or a multi-stage polishing method by changing the direction of polishing head of chemical mechanical polishing device but replacing different polishing platens for processing. The invention can eliminate the rotation effect after wafer polishing and achieve better alignment accuracy.

Description

Five 'invention description (1) 5-1 Field of the invention: The present invention relates to a method for changing the direction of a wafer grinding mechanism or a grinding table used in a semi-conductor to increase the precise alignment of a yellow light alignment machine. Or the replacement is not 1. This is accomplished in particular by the grinding head segment grinding. ’Grinding platform, in conjunction with the background of multi-2 invention. Come to flatten the flattening technology of potassium hydroxide or ammonia, but various process parameters. Grinding surface is up to 100. Basically chemical grinding. Grinding table (H e a d) The front side of the wafer group is pressed against chemical mechanical polishing. The continuous delivery to the grinding technology is currently using a kind of grinding slurry (combined with I Luhe). One is to provide the back side of the wafer chemical machine wafer, and the upper side is used to carry out the f (⑽) process along the conveying pipe. Polyhedronization " 2: 2: The Hiragaki process used. This = the principle of grinding, combined with the appropriate contours of high and low fluctuations, = solutions such as hydrogen peroxide (H2O2) are properly controlled, the chemical mechanical polishing process can be divided A flatness of more than ninety-four. A mechanical grinder consists of one for crystals and one or several for grasping and grinding. In operation, the polishing head grasps the wafer and is covered with a layer of polishing pad (Pad). Grinding table when CMP is performed,

G: \ shawdon \ shawdon98 \ patent \ D870U_TW1. Hengd4 Page 5. Invention Description (2) At this time, the chemical mechanical polishing is to use the chemical reaction provided by the slurry and the mechanical polishing of the wafer on the polishing table. A planarization technique that removes protruding deposits on a wafer step by step. But this seemingly simple flattening technique is very difficult to control. Mainly because people know too little about this process combining chemical reaction and mechanical grinding. Among them, mechanical grinding is used, such as the pressure of the wafer, and the type of the rotation speed has a great influence. And fixing a single polishing direction ’often causes a poor Rotation Effect to the subsequent yellow light alignment process. 5-3 Purpose and Summary of the Invention: The purpose of the present invention is to eliminate the rotation effect generated on the wafer surface by the chemical mechanical polishing mechanism. This rotation effect causes the wafer to have poor alignment accuracy during the subsequent yellow light alignment process, resulting in misalignment and loss of wafer yield (Y i e 1 d). According to the above-mentioned object, the present invention provides an improved method for a semiconductor wafer polishing machine. The steps at least include: the wafer device is mounted on a polishing platform device of the chemical mechanical polishing mechanical device; the polishing head is accurately ground in a first rotation direction relative to the polishing platform of the chemical mechanical polishing device to grind the wafer; The grinding platform of the chemical mechanical polishing device is exactly opposite to the second direction in a second direction, wherein the first direction is opposite to the second direction, and it also includes repeating the first direction.

G '\ shawd〇n \ shawdcm98 \ patent \ D87014_TWl · misd5 Page V. Description of the invention (3) Grinding and grinding in the second direction mentioned above The method of the second grinding device and device provided by the present invention is as follows: The first grinding platform of the mechanical grinding mechanical device; the grinding in which the first direction of the second grinding platform relative to the chemical mechanical grinding device is opposite to the first direction of the second party and the third grinding device provided by the above-mentioned second invention Method, the steps from which the first direction of the chemical mechanical polishing mechanical device is relative to the chemical mechanical polishing of the semiconductor wafer; the wafer is moved to a table, and the polishing head accurately uses a second and second polishing platform to grind the crystal direction; The wafer is moved to a third grinding head, which is accurately opposed to the grinding table in the first direction to grind the wafer. At the same time, the polishing of the table and the second polishing table are used as the semiconductor wafer chemical machinery > & &: the semiconductor wafer is mounted on the chemical polishing table; the wafer is moved to a second position; the polishing head is accurately positioned in a second direction. The two grinding platforms grind the wafer, and further include repeatedly performing grinding in the above direction. ^ Semiconductor wafer chemical machinery includes: mounting the semiconductor wafer on a polishing platform; the grinding head accurately uses the first polishing platform of the first device to grind the second polishing platform, and is opposite to the chemical mechanical polishing device in the direction of the second polishing plane. Tablets, where the first direction is opposite to the second grinding platform; on the third grinding platform, the third study on the chemical mechanical polishing device further includes grinding repeatedly performing the first grinding described above, and the third grinding platform 5- 4 schema brief description:

5. Description of the invention (4) Figure A shows the schematic diagram of the chemical mechanical polishing process with a single grinding head. The first diagram B shows a schematic diagram of a chemical mechanical polishing process with dual grinding heads. The first diagram C shows the schematic diagram of the chemical mechanical polishing process with three grinding contacts. The second diagram A shows the principle of the A1 ignment Accuracy test device. The second graph B shows the results of the alignment accuracy test device. The third A graph shows the results obtained by the prior art. Figure 3B shows the results obtained by the present invention. Representative symbols in the figure: 10 semiconductor wafer 12 grinding platform 14 grinding head 20 chemical mechanical grinding mechanical device 21 semiconductor wafer 22 first grinding platform 24 grinding head 26 second grinding platform 30 chemical mechanical grinding mechanical device 31 first grinding Table 34 Grinding head 36 Second grinding table

G: \ shawdon \ shawdon98 \ patent \ D87014—TW1 · Law d7 Page V. Description of the invention (5) 38 The third grinding platform 40 metal layer 44 distance from '5 Detailed description of the invention: The present invention is provided with a grinding W coat, to As shown in Figure A, its step is to first polish the semi-conducting grinding head of the semiconductor mechanical device's grinding mechanical grinding device in the clockwise direction. Invented the semiconductor wafer 21 with a grinding head device 2 4 agricultural spindle clockwise 'in cooperation with the appropriate research on a kind of yellow light alignment machine for the following description of the wafer 10 with a horizontal head 1 4; then clockwise spindle rotation For the polishing direction, the body wafer 10 is connected to the counter-clockwise wafer 10 of the chemical mechanical research platform 12. After that, the first embodiment of the clock polishing is horizontally mounted on the substrate; the polishing head 2 4 rotates in the direction, and the first abrasive and the polishing pad are used as a method for precise alignment of the semiconductor wafer chemical mechanical research. The direction of the head 1 4 turns, with proper cooperation, it can be repeated about half in the clock direction of the pre-grinding device. The same main axis is used as the time B for grinding the two items, and the grinding direction of the grinding machine for the chemical table 22 is mechanically polished. Compared to the chemical polishing platform 12 and the polishing pad platform, the clock is rotated in the square grinding direction to follow the steps. It is shown that firstly, the first mechanical grinding of the device 20 is performed in a clockwise direction to grind the semiconductor. 5. Description of the invention (6) the body wafer 21; and then in the second grinding s. For the chemical mechanical polishing device; In the counterclockwise direction of the polishing table 26, == is the second frame, which is used as a polishing direction to polish the semiconductor wafer 21. t-grinding For the third embodiment of the present invention, for example, the conductor wafer 31 is horizontally loaded on the wafer and No, I will fight the semi-grinding ten agriculture on the first thousand ^ 32 of the mechanical grinding mechanism 30. The grinding head 34 is accurate relative to the chemical mechanical grinding. At A is also the clock of the first grinding platform. Direction No .: grinding the semiconductor wafer 31; then move the wafer 31 to the first-polishing flat port 36, and on the second grinding platform 36, the grinding head is accurately ground in a counterclockwise direction relative to the main axis of the chemical mechanical polishing device, L: 3; 3ni; T rotation direction, as grinding = 'Finally on the third grinding platform 38, the grinding head accurately uses the clockwise rotation direction with respect to the spindle of the chemical mechanical polishing device, that is, = clockwise rotation direction of the grinding platform' The grinding direction is to grind the half soil piece 31. The total grinding time of the first grinding platform and the third grinding platform accounts for about half of the total grinding time, and the grinding time of the second platform accounts for about the other half. The effect is reduced to a minimum, and even the rotation effect of grinding is eliminated. Thus, a smooth and smooth semiconductor wafer can be obtained, and the alignment accuracy of the subsequent yellow light alignment machine can be increased. The effect of wafer grinding can be aligned accuracy. ) The test device was obtained experimentally, and its measurement pattern is shown in Figure 2a. Its principle is as follows: 、 G: \ shawdon \ shawdon98 \ patent \ D87014—TW1. Brother d9 Page V. Description of the invention (7 ) (a) Accurate alignment measurement is the measurement position. For example, it is set on the four sides of the semiconductor wafer as the layer 42. Accurate alignment measurement—the layer is the contact layer 40 'The second layer is the metal distance 44.' Immediately measure (b) the precise alignment measurement between the contact layer 40 and the metal layer 42 as shown in Figure B. Blindly set the positive and negative (+ or ―) of the four quadrants. (C) Each Mask measurement with precise alignment In the field, about seven points of values can be obtained. The results and the grinding of the present invention: κ = grinding wafer obtained by the previous technology test Table 1 and Table 2: 3 results on the day, and the obtained values are listed in the following table One: X-axis and X-axis

Mean (average) 9.7

Max 9.4 74 ~ 7 Min 3 〇 (Minimum) -116.7 14 0.3 -110.4 Π 113.5 'Table

Mean Max Min 3 〇 (average value) (maximum value) (minimum value) X axis ^ 4.1 ~ 3 5.0 ~ -54.0 50.6 ~ Y axis 9.1 67.2 -46.1 68.3

G: \ shawdon \ shawdon98 \ patent \ D87014_TW1. Cone dl0 Page V. Description of the invention (8) The average value, maximum value, and comparison of the data shown above * In the X axis, the value of 3 σ is more than in the prior art. The present invention The average value has also been greatly improved.

The prior art and the present invention have X and γ red A minimums and 3 σ values. If these numbers 丄 =, the average value, the maximum value, and the yin of the present invention are taken as, and small values are greatly improved. In the Y axis, the same, maximum, minimum, and 3 σ values are more respectful. The different techniques show that before grinding, the present invention can be applied to packages including Westech, Syatems Strasbaugh, and Presi. It is only within the scope of equivalent modification of the patent application of the present invention. . The third and third pictures A and B are illustrated by the method of uniformity and uniform distribution after grinding ^ Including various types of grinding machinery such as

Fujikoshi, Cybeq Systems, 'SpeedFam and AMAT. It is only a preferred embodiment of the present invention, and is not intended to limit the scope. 'All other old or modified without departing from the present invention' should be included in the following application G: \ shawdon \ shawdon98 \ patent \ D87014_JWl.heng dll page

Claims (1)

6. Applying for a patent Fangu 1. A square i device used for precise alignment of semiconductor wafers on a yellow light alignment machine to enhance the crystal placement of the wafer device in a chemical mechanical grinding machine 2: at least includes: Grinding head 4 is a grinding platform set by 篦 — 浐 丝士 人 4, π silly + 峄 is a grinding platform opposite to the first slave rotation direction to grind the wafer; and a mechanical polishing device is used for grinding On the platform, the grinding head accurately uses the grinding platform of the chemical mechanical grinding device ... the = in the first direction, thereby reducing the rotation effect of the grinding and reducing the rotation effect of the grinding. Take it low or even go 2. The method according to item 1 of the patent application range, wherein the grinding time in the first direction is approximately equal to the grinding time in the second direction. 3. The method according to item 1 of the scope of patent application, wherein the above-mentioned grinding head is exactly in the first direction relative to the grinding platform of the chemical mechanical grinding device, and its direction is clockwise or counterclockwise. 4. The method according to item 3 of the scope of patent application, wherein the above-mentioned grinding contact is precisely in the second direction relative to the grinding platform of the chemical mechanical grinding device, and its direction is the counterclockwise or clockwise direction. 5. The method according to item 1 of the scope of patent application further includes repeatedly performing the grinding in the first direction and the grinding in the second direction. G: \ shawdon \ shawdon98 \ patent \ D87014_TWl. 掰 dl2 A method for improving the precise alignment of a semiconductor wafer chemical mechanical polishing device by using a semiconductor wafer chemical mechanical polishing device in Huangxian == ^, the steps of which include at least: The first grinding flat grinding head of the chemical mechanical grinding mechanical device is accurate ~ grinding flat A universal relative to the twentieth D of the chemical mechanical grinding device to grind the wafer; the wafer is handled as a second grinding platform 5 __ as a second grinding platform The boat is in the second grinding plane twenty-three, and in the chemical mechanical grinding; set it; the helical grinding head is broken in a direction opposite to the second grinding platform of the flute— 衮 罝 to grind the wafer, " 〇 " —The direction is opposite to the second direction. Yanxiang Xiangfang 1 The first time mentioned in the middle of the above 0, at the time, the method of grinding the party Xiangxiang Xiangfang 6 Second, the encirclement of the contract, and other special treaties please Dashenjian as time 7. Grind phase ;;: ί The method of item 2 of range 2, wherein the above-mentioned grinding head is exactly in the first direction of the first grinding stage of the chemical mechanical grinding device, and its direction is clockwise or counterclockwise. π 傲 卞 兵 9. The second direction of the second grinding platform of the chemical-mechanical grinding device, as described in item 8 of the patent application scope, is the direction of the counterclockwise or clockwise direction. 〃 10. For example, the scope of 46 of t 4 patent & includes repeated grinding in the first direction and grinding in the above second direction. G: \ shawdon \ shawdon98 \ patent \ D870l4jTWl.heng dl3 pages 6. Scope of Patent Application J. A method used as a chemical mechanical polishing device for semiconductor wafers to improve the precise alignment of wafers on a yellow light alignment machine. The steps include at least the first grinding step to place the semiconductor wafer device on the wafer. Chemical mechanical polishing mechanical platform;-The polishing head is accurately ground in the first direction relative to the first-polishing platform of the chemical mechanical polishing device to grind the semiconductor wafer; Move the wafer to a second polishing platform, and in the second On the grinding plane A, the grinding head accurately grinds the wafer in a second direction relative to the first grinding stage of the chemical mechanical polishing device, wherein the first direction is opposite to the first direction; the wafer is moved to a first Three grinding platforms; and on the third grinding platform, the grinding head is accurately opposed to the third grinding platform of the chemical mechanical grinding device in the first direction to grind the wafer. 12. The method according to item 11 of the scope of patent application, wherein the above-mentioned grinding head is exactly in the first direction relative to the grinding platform of the chemical mechanical grinding device, and its direction is clockwise or counterclockwise. 1 3. The method according to item 12 of the scope of patent application, wherein the above-mentioned grinding head is exactly in a second direction relative to the second grinding platform of the chemical mechanical grinding device, and its direction is a counterclockwise or clockwise direction. G: \ shawdon \ shawdon98 \ patent \ D87014-TW1. Shang dl4 Page 6. Application for Patent Scope 14. If the method of the scope of application for item No. 11 further includes repeatedly performing the grinding of the above-mentioned first grinding platform, the second grinding platform Grinding of the third grinding platform. G: \ shawdon \ shawdon98 \ patent \ D87014_TWl.heng dl5 pages