CN113458995A

CN113458995A - Flip-chip polytetrafluoroethylene semiconductor wafer anchor clamps

Info

Publication number: CN113458995A
Application number: CN202110674881.5A
Authority: CN
Inventors: 兰添翼; 赵水平; 田启智; 王妮丽
Original assignee: Shanghai Institute of Technical Physics of CAS
Current assignee: Shanghai Institute of Technical Physics of CAS
Priority date: 2021-06-18
Filing date: 2021-06-18
Publication date: 2021-10-01

Abstract

The invention discloses a flip-chip polytetrafluoroethylene semiconductor wafer clamp which can clamp a semiconductor wafer in an inverted mode and comprises a clamp main body, a clamp bottom plate, a nut and a screw. A cavity is designed in the center of the clamp body and used for placing a semiconductor wafer. In order to prevent the inverted wafer from falling off, a jig base plate is designed. The center of the bottom plate of the clamp has a central through hole, and the diameter of the central through hole is smaller than that of the semiconductor wafer. The clamp main body is connected with the clamp bottom plate through four screw rods. In addition, the length of the screw is far greater than the sum of the lengths of the fixture main body fixing through hole and the fixture bottom plate fixing through hole, the top end of the screw protrudes out of the fixture bottom plate to play a role of a supporting leg, and the design is favorable for solution exchange through the center through hole of the fixture bottom plate, so that the solution reaction efficiency is improved.

Description

Flip-chip polytetrafluoroethylene semiconductor wafer anchor clamps

Technical Field

The invention relates to a semiconductor photoelectric detector manufacturing technology, in particular to a clamp applied to wafer surface treatment.

Background

The photoelectric detector is manufactured by a semiconductor wafer through processes of multi-step photoetching, film growing, etching, cleaning, polishing, scribing and the like. In the wafer manufacturing process, cleaning or floating after each step of photoetching is an important process. The process involves clamping the wafer. Researches show that compared with a mode that the wafer is vertically arranged or the front side of the wafer is upwards clamped, the inverted clamping mode can reduce the surface defects of the wafer and improve the yield of the detector.

Conventional wafer chucks use a vertical or right side up orientation to position the wafer in a vertical or horizontal slot. The clamping mode of the clamp cannot solve the problem that after the photoresist is removed, a small amount of pollutants such as particles, fibers, organic matters or metal films and the like on the photoresist are adhered to the surface of the wafer, and the pollutants are difficult to remove from the surface of the semiconductor wafer under the action of electrostatic adsorption, so that various defects are generated on the surface of the wafer, and the yield of the manufactured detector is reduced.

Disclosure of Invention

The purpose of the invention is as follows: the problem that pollutants are possibly brought to the surface of a wafer by a clamping mode of a conventional clamp in the process of photoresist floating or wafer cleaning is solved. Therefore, the inverted polytetrafluoroethylene semiconductor wafer clamp is designed. The clamp only contacts a 1 mm-2 mm circular ring area at the edge of the semiconductor wafer, and other effective areas on the surface of the wafer are not damaged at all. The central through hole of the clamp bottom plate and the longer support screw design also facilitate the solution exchange on the wafer surface. In addition, the cleaning or glue floating effect of the wafer can be greatly improved by matching ultrasonic or megasonic cleaning.

The technical scheme of the invention is as follows:

the clamp comprises a clamp main body, a clamp bottom plate, a nut and a screw rod, wherein the clamp main body and the clamp bottom plate are fixed together through the nut and the screw rod. The clamp body comprises a clamp body fixing through hole for mounting the screw rod and a cavity for placing the wafer. The clamp bottom plate comprises a clamp bottom plate fixing through hole and a central through hole, wherein the clamp bottom plate fixing through hole is provided with a screw rod. The inner diameter of the concave cavity on the clamp body is determined according to the diameter of the clamped wafer and can be 0.5 mm-1.0 mm larger than the diameter of the semiconductor wafer. The depth of the cavity is determined according to the thickness of the clamped wafer and can be 5.0-10.0 μm larger than the thickness of the semiconductor wafer. The diameter of the central through hole on the bottom plate of the clamp is 1.0 mm-2.0 mm smaller than the diameter of the semiconductor wafer.

The semiconductor wafer is arranged in a concave cavity in the center of the clamp main body, the inner diameter of the concave cavity is 0.5-1.0 mm larger than the diameter of the wafer, and the depth of the concave cavity is 5.0-10.0 mu m larger than the thickness of the wafer. A certain number of main body fixing through holes are uniformly distributed on the periphery of the concave cavity of the clamp main body, and positioning grooves are formed in the edge positions of the front side of the clamp main body.

To hold the inverted semiconductor wafer in the pocket, a chuck base plate is designed. The clamp bottom plate is connected with the clamp main body through four screws, and simultaneously clamps the wafer in the concave cavity. The diameter of the clamp bottom plate is the same as that of the clamp main body, a central through hole is formed in the center of the clamp bottom plate, and the diameter of the central through hole is smaller than the diameter of the wafer by 1.0-2.0 mm. Bottom plate fixing through holes are uniformly distributed around the through holes of the clamp bottom plate, and the bottom plate fixing through holes correspond to the clamp main body fixing through holes in number, diameter and direction one by one. The edge of the bottom plate of the clamp is provided with positioning bosses which correspond to the positioning grooves on the side of the main body of the clamp one by one, and the positioning bosses can be completely embedded into the positioning grooves.

Furthermore, a square concave cavity is formed in the circular edge of the concave cavity of the clamp main body, so that the tweezers can conveniently clamp the wafer.

Furthermore, the screw rod is connected with the clamp main body and the clamp bottom plate, so that the clamp main body and the clamp bottom plate are connected, and the screw rod also has the purpose of a positioning pin.

Furthermore, the central through hole of the bottom plate of the clamp and the longer screw rod can support the clamp at a certain height, so that the exchange between the surface of the wafer and the solution is improved.

Further, the diameter of the clamp main body is the same as that of the clamp bottom plate, and the circle centers of the clamp main body and the clamp bottom plate correspond to each other. The concave cavity of the clamp main body corresponds to the center of the center through hole of the clamp bottom plate.

Drawings

The drawings that are required to be used in the description of the embodiments will now be briefly described. The drawings described below are only embodiments of the invention, and other drawings can be derived from them without inventive effort.

FIG. 1 is a cross-sectional view of a flip-chip PTFE semiconductor wafer holder of the present invention;

wherein: 1 is a clamp main body, 2 is a clamp bottom plate, 3-position nuts, 4 is a screw, 1-1 is a clamp main body fixing through hole, 2-1 is a clamp bottom plate fixing through hole, 1-2 is a clamp main body concave cavity, and 2-2 is a clamp bottom plate central through hole.

Detailed Description

The present invention will be described in further detail with reference to specific examples.

First, the examples described herein are specific embodiments of the present invention, are intended to illustrate the concept of the present invention, are illustrative and exemplary, and should not be construed as limiting the embodiments of the present invention and the scope of the present invention. In addition, other technical solutions which are obvious for a person skilled in the relevant art based on the disclosure of the present claims and the specification can be adopted, and the technical solutions comprise the solutions adopting any obvious replacement or modification of the embodiments described herein.

Next, the drawings of the present specification are only for illustrating a schematic view of the inventive concept, and are only for illustrating the interrelationship between the respective components. The above schematic diagrams are merely examples, which should not limit the scope of the present invention herein.

FIG. 1 is a schematic view of a flip-chip type PTFE semiconductor wafer chuck according to the present invention, which comprises a chuck body, a chuck base plate, a nut, and a screw. The semiconductor wafer is positioned between the fixture body cavity 1-2 and the fixture bottom plate central through hole 2-2.

The fixture main body 1 is of a disc structure as a whole and comprises a concave cavity 1-2 and a main body fixing through hole 1-1. The concave cavity 1-2 is a circular shallow pit, and the circle center of the concave cavity is overlapped with that of the clamp main body. If the semiconductor wafer has a diameter of 50mm and a thickness of 350 μm, the diameter of the cavity 1-2 is designed to be 50.5mm to 51.0mm, and the depth of the cavity 1-2 is designed to be 355 μm to 360 μm. And main body fixing through holes 1-1 are formed around the concave cavity 1-2. The clamp bottom plate 2 is of a hollow cylindrical structure and comprises a fixing through hole 2-1 and a central through hole 2-2. The circle center of the central through hole 2-2 coincides with the circle center of the clamp bottom plate. The fixture bottom plate fixing through holes 2-1 and the fixture main body 1 fixing through holes 1-1 are in one-to-one correspondence, and the number and the positions of the fixing through holes need to be kept consistent. The diameter of the central through hole 2-2 of the clamp bottom plate 2 is designed to be 48 mm-49 mm.

The semiconductor wafer holder is typically a teflon material.

The specific implementation mode of the clamp is as follows:

the semiconductor wafer is firstly placed on the cavity 1-2, the back of the wafer is opposite to the cavity 1-2, then the clamp bottom plate 2 is covered on the clamp main body 1, the clamp main body 1 and the clamp bottom plate 2 are screwed together by the nut 3 and the screw rod 4, and then the clamp can be placed in a solution for subsequent process treatment.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and the above-mentioned specific embodiment is only one possible operation example, and any other products in various forms can be designed according to the teaching of the present invention, but any changes in the shape or structure thereof, which have the same or similar technical solutions as the present application, fall within the protection scope of the present invention.

Claims

1. The utility model provides a flip-chip polytetrafluoroethylene semiconductor wafer anchor clamps, includes anchor clamps main part (1), anchor clamps bottom plate (2), nut (3) and screw rod (4), its characterized in that, flip-chip semiconductor wafer anchor clamps main part (1) and anchor clamps bottom plate (2) are fixed together through nut (3) and screw rod (4).

2. The clamp for the flip-chip polytetrafluoroethylene semiconductor wafer according to claim 1, wherein said clamp body (1) is a circular disk having four body fixing through holes (1-1) formed around the periphery thereof, a cavity (1-2) for holding the semiconductor wafer is formed in the center of the clamp body (1), the inner diameter of the cavity (1-2) is 0.5mm to 1.0mm larger than the diameter of the semiconductor wafer to be cleaned, and the depth of the cavity (1-2) is 5.0 μm to 10.0 μm larger than the thickness of the semiconductor wafer to be cleaned.

3. The clamp for a semiconductor wafer of inverted polytetrafluoroethylene according to claim 1, wherein said clamp base plate (2) is a circular disk having four base plate fixing through holes (2-1) formed around the periphery thereof, and a center through hole (2-2) for passing a cleaning solution is formed in the center of the clamp base plate (2), and the diameter of said center through hole (2-2) is smaller than the diameter of the semiconductor wafer by 1.0mm to 2.0 mm.