CN115483145A

CN115483145A - AOI's wafer adsorption equipment and AOI equipment suitable for carborundum FAB factory

Info

Publication number: CN115483145A
Application number: CN202210933725.0A
Authority: CN
Inventors: 王旭东
Original assignee: Zibo Lvnengxinchuang Electronic Technology Co ltd
Current assignee: Zibo Lvnengxinchuang Electronic Technology Co ltd
Priority date: 2022-08-04
Filing date: 2022-08-04
Publication date: 2022-12-16

Abstract

The invention provides an AOI wafer adsorption device and AOI equipment suitable for a silicon carbide FAB factory, which comprise: adsorb the mesa, the upper surface that is used for adsorbing the wafer on the absorption mesa of AOI equipment sets up a plurality of PV holes, the PV hole sets up in adsorbing mesa edge, lies in the outward flange department of adsorbing the mesa on AOI equipment and sets up a plurality of ejector pin lift holes that are used for going up and down the wafer. The invention cancels the PV groove on the traditional silicon wafer AOI equipment, and arranges the PV hole at the edge of the upper surface of the adsorption table board, thereby solving the interference of the PV groove on the quality detection of the silicon carbide wafer and not influencing the adsorption effect on the silicon carbide wafer.

Description

AOI's wafer adsorption equipment and AOI equipment suitable for carborundum FAB factory

Technical Field

The invention relates to the field of semiconductor processing, in particular to a wafer adsorption device and AOI equipment suitable for AOI of a silicon carbide FAB factory.

Background

AOI equipment, also known as AOI optical automatic detection equipment, has become an important detection tool and process quality control tool for ensuring product quality in the electronic manufacturing industry, and during wafer (wafer) production, the AOI equipment is required to fix a wafer for shooting detection. The chuck for the AOI equipment used in the 12-inch silicon wafer FAB FAB would have an installed PV cavity with a PV hole in it, and the wafer would be sucked by the negative pressure through the PV hole and the PV cavity, as shown in FIG. 1. When being applied to emerging carborundum FAB factory, the size of carborundum wafer is 6 cun usually at present, because carborundum wafer is transparent compared with the silicon wafer to carborundum wafer's size is obviously less than the silicon wafer size, and the step-like shade of PV recess can be shot into with carborundum wafer together when being shot by AOI equipment, leads to the wafer image in the photo to have the annular seal of a circle PV recess, when analysis detects the defect, can be with this annular seal false detection, influence the measurement.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a wafer adsorption device suitable for AOI of a silicon carbide FAB factory and AOI equipment.

The invention provides a wafer adsorption device suitable for AOI of a silicon carbide FAB factory, which comprises: adsorb the mesa, the upper surface that is used for adsorbing the wafer on the absorption mesa of AOI equipment sets up a plurality of PV holes, the PV hole sets up in adsorbing mesa edge, lies in the outward flange department of adsorbing the mesa on AOI equipment and sets up a plurality of ejector pin lift holes that are used for going up and down the wafer.

Preferably, the number of the PV holes is 3, and the PV holes are uniformly distributed on the inner side of the edge of the adsorption table top.

Preferably, the number of the mandril lifting holes is 3, the mandril lifting holes are uniformly distributed on the outer side of the edge of the adsorption table board, and the mandril lifting holes and the PV holes are arranged in a staggered mode.

Preferably, the upper surface of the adsorption table top is a gray frosted ceramic surface.

Preferably, the size of the upper surface of the adsorption table top is smaller than that of a 6-inch silicon carbide wafer, and the PV hole and the mandril lifting hole are located in an annular mounting invalid region with the width of 1-2cm at the edge of the adsorbed silicon carbide wafer.

The AOI equipment suitable for the silicon carbide FAB factory comprises a wafer adsorption device suitable for the AOI of the silicon carbide FAB factory.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention cancels the PV groove on the traditional silicon wafer AOI equipment, and arranges the PV hole at the edge of the upper surface of the adsorption table board, thereby solving the interference of the PV groove on the quality detection of the silicon carbide wafer and not influencing the adsorption effect on the silicon carbide wafer.

2. According to the invention, the gray frosted ceramic surface is arranged on the upper side surface of the adsorption table top, the gray processing is required for the picture taken during the detection of the silicon carbide wafer, and the gray frosting can enable the silicon carbide wafer to be easily debugged to about 110 gray scale values under the illumination of AOI (automated optical inspection), so that the silicon carbide wafer has very strong identification capability for bright and dark defects below 50 or above 200, the identification degree is improved, and the condition of missed detection is reduced.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

FIG. 1 is a top view of a prior art adsorption apparatus;

FIG. 2 is a bottom view of a conventional adsorption apparatus;

FIG. 3 is a top view of a wafer chuck device according to the present invention;

fig. 4 is a bottom view of the wafer adsorbing device disclosed in the present invention.

Description of the reference numerals:

PV groove 101 PV hole 201

PV suction hole 102 ram lift hole 202

Liftpin lifting hole 103 gray frosted ceramic surface 203

Ceramic upper surface 104

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.

The invention discloses an AOI wafer adsorption device suitable for a silicon carbide FAB factory, which is improved based on an adsorption device on the existing silicon wafer AOI equipment, and referring to fig. 1, the existing 12-inch silicon wafer adsorption device comprises a PV groove 101, wherein the PV groove 101 is provided with a plurality of annularly-arranged grooves which are communicated through three middle straight-line grooves, 3 PV suction holes 102 are arranged in the annularly-arranged grooves, and the wafer is sucked through the negative pressure of the PV groove 101 and the PV suction holes 102. The upper surface of the adsorption device is a ceramic upper surface 104, a plurality of lift pin lifting holes 103 are further formed in the surface of the adsorption device, and the lift silicon wafer can lift silicon wafers, but the current silicon carbide wafer can only achieve 6 inches at home and abroad, and can be adsorbed without large-area adsorption PV grooves.

The invention discloses a wafer adsorption device suitable for AOI of a silicon carbide FAB factory, which comprises the following components: adsorb the mesa, be used for adsorbing the upper surface of wafer to set up a plurality of PV holes 201 on the absorption mesa of AOI equipment, PV hole 201 sets up in adsorbing mesa edge, and the outward flange department that lies in the absorption mesa on AOI equipment sets up a plurality of ejector pin lift holes 202 that are used for going up and down the wafer. The number of the PV holes 201 is 3, and the PV holes 201 are uniformly distributed on the inner side of the edge of the adsorption table top. The number of the mandril lifting holes 202 is 3, the mandril lifting holes 202 are uniformly distributed on the outer side of the edge of the adsorption table board, and the mandril lifting holes 202 and the PV holes 201 are arranged in a staggered mode.

The size of the upper surface of the adsorption table top is smaller than that of a 6-inch silicon carbide wafer, and the PV hole 201 and the ejector rod lifting hole 202 are located in an annular mounting invalid region with the width of 1-2cm at the edge of the adsorbed silicon carbide wafer. The PV holes 201 and the PV grooves in the middle of the adsorption table top are eliminated, the PV holes 201 are transferred to the edge of the adsorption table top, and the ejector rod lifting holes 202202 which push against the silicon carbide wafer are placed outside the adsorption table top due to the fact that the radius of the adsorption table top is reduced, so that the fact that the stamps of the ejector rod lifting holes 202 and the PV holes 201 enter the AOI photographing process is avoided.

Because silicon carbide is currently used as a power device, die width of crystal grains on a wafer is large, die on the edge is incomplete, and an invalid area of more than 1cm on the edge of the wafer is free of die, the modification does not have important influence on the practice. The PV holes 201 are moved to the edge area of the adsorption table, so that the measurement can be normally performed as long as the edge is removed and no detection is performed. The normal wafer id is beaten at the flat edge, and the position of about 2cm can be obtained, and almost most active regions of the whole wafer can be normally tested only by planing off invalid regions of the edge of the wafer and measuring and removing the width of the edge.

The upper surface of the adsorption table top is a gray frosted ceramic surface 203. The grey frosting is used because: the defect detection of the AOI equipment adopts the principle of processing the gray scale of a photo after the photo is taken. The gray scale value is 0-255, the silicon carbide product can be easily debugged to the gray scale value of about 110 under the light of AOI by using gray frosting, so that the light and dark defects below 50 or above 200 are very strong in identification capability, the non-defect area (about 110 gray scale) is not subjected to false detection or false detection and is very small, the original adsorption table top is difficult to debug without using gray frosting, even if the light intensity is greatly increased, the effect cannot be achieved, the silicon carbide wafer can be integrally positioned at a higher gray scale or a lower gray scale (for example, when the defect is 55 gray scale, the defect is missed to be detected), and the false detection rate is increased. Therefore, the new adsorption table reduces the false detection rate and the missing detection rate.

The improved adsorption table top can effectively reduce the false detection rate when the defect detection is normally carried out on the silicon carbide wafer, and is favorable for researching the yield of products. Defects can be monitored on each layer of the product, so that the defect type and how the defect type is generated are influenced by poor electrical performance and poor yield of the product. The false detection rate of the prior adsorption table top is too high, the tracing problem can be influenced under the condition of PV influence, and the defect which really has problems is missed to be detected. And the AOI can photograph the defects, and if the false detection is too much, a huge amount of time is spent on performing invalid photographing, so that the measurement time is seriously influenced.

The improved method has more positive significance in that after the missing detection and the false detection are reduced, the defects have the capability of controlling, after one process, the defects are measured in time and detected, whether the process of the process is qualified or not can be measured, when the process is detected to be poor, the damage can be stopped in time and reworked, a plurality of layers of processes exist, the processes cannot be reworked after being processed for several layers, and only the processes can be scrapped, so that the accurate detection of the defects is very important.

The invention also discloses AOI equipment suitable for the silicon carbide FAB factory, which comprises the wafer adsorption device suitable for the AOI of the silicon carbide FAB factory.

In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present application.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.

Claims

1. A wafer adsorption apparatus suitable for AOI of a silicon carbide FAB factory, comprising: adsorb the mesa, the upper surface that is used for adsorbing the wafer on the absorption mesa of AOI equipment sets up a plurality of PV holes, the PV hole sets up in adsorbing mesa edge, lies in the outward flange department of adsorbing the mesa on AOI equipment and sets up a plurality of ejector pin lift holes that are used for going up and down the wafer.

2. The wafer adsorption device of AOI equipment suitable for silicon carbide plants of claim 1, wherein: the number of the PV holes is 3, and the PV holes are uniformly distributed on the inner side of the edge of the adsorption table top.

3. The wafer adsorption device of AOI equipment suitable for silicon carbide plants of claim 1, wherein: the number of the ejector rod lifting holes is 3, the ejector rod lifting holes are uniformly distributed on the outer side of the edge of the adsorption table board, and the ejector rod lifting holes and the PV holes are arranged in a staggered mode.

4. The wafer adsorption device of AOI equipment suitable for silicon carbide plants of claim 1, wherein: the upper surface of the adsorption table top is a gray frosted ceramic surface.

5. The wafer adsorption device suitable for AOI of silicon carbide FAB factory according to claim 1, wherein: the size of the upper surface of the adsorption table top is smaller than that of a 6-inch silicon carbide wafer, and the PV hole and the ejector rod lifting hole are located in an annular mounting invalid area with the width of 1-2cm at the edge of the adsorbed silicon carbide wafer.

6. An AOI device suitable for a silicon carbide FAB plant, comprising: a wafer adsorption apparatus comprising an AOI suitable for use in a silicon carbide FAB plant as claimed in any one of claims 1 to 5.