Device and method for acid etching to remove surface damage of silicon wafer

Abstract

The invention discloses a device and a method for eliminating surface damage of a silicon wafer through acid etching. The device comprises a carrier, a manipulator, an etching process tank and an acid mixing tank, wherein the carrier comprises two side plates and fixing rods fixedly supported between the two side plates; a carrier center driving shaft, a carrier center driving gear and a carrier driving gear are mounted on each of the two side plates; carrier fixing sleeves are mounted on the carrier center driving shafts; three toothed rotating rods are further mounted between the two side plates; toothed rotating rod transmission gears matched with the carrier center driving gears are arranged at the two ends of each toothed rotating rod; the manipulator comprises carrier locking parts locked with the fixing sleeves on the two sides of the carrier, and further comprises a mechanical arm transmission gear set, a carrier driving motor and two carrier transmission gear sets; the bottom of the etching process tank is connected with the acid mixing tank through an acid liquid circulating liquid inlet pipe; the etching process tank is provided with an overflowing tank; the overflowing tank is connected to the acid mixing tank through an acid liquid circulating liquid returning pipe. The device can greatly reduce the incidence of etching marks and improve the surface uniformity of an etched wafer.

Description

technical field [0001] The invention relates to a device and method for removing surface damage of silicon wafers by acid etching, which is suitable for peeling damage corrosion processing after cutting and grinding of silicon wafers with 4, 5, 6, and 8 inches. Background technique [0002] In the process of wafer processing, after the wafer undergoes mechanical processing such as slicing and grinding, a certain depth of damage layer is formed on the surface of the wafer due to the stress generated by mechanical processing. Chemical etching is usually used to remove the mechanically damaged layer. The corrosion process generally consists of acid corrosion and alkali corrosion. The alkali etching process is easy to control the flatness due to its low corrosion rate, but the surface is rough and easy to absorb impurities. The acid etching process has a high corrosion rate, the surface is relatively bright, and it is not easy to absorb impurities, but the surface flatness is ...

AI Technical Summary

Problems solved by technology

Its advantage is that it not only realizes the movement of the silicon wafer, but also the relative movement of the silicon wafer relative to the carrier, and it is not easy to leave corrosion marks; its disadvantage is that the carrier itself does not move, so the huge carrier will interfere with the flow of the etchant. Therefore, it is easy to cause local swirl of etchant, affecting the flatness of silicon wafer

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