Method and device for removing cut oxidation films of 8-inch wafers

Abstract

The invention provides a method and device for removing cut oxidation films of 8-inch wafers. The method comprises the steps as follows: (1) silicon wafers are sorted by a sorting machine, cuts vertically face downwards; (2) wafer boxes are arranged on a positioning clamp groove, and are covered by a nitrogen protection cover; (3) a motor is started, and a screw drives a lifting tank to be lifted upwards from an HF acid liquor tank; (4) when an etching block is tightly contacted with each silicon wafer cut, HF acid reacts with the oxidation films; (5) a motor is started, and the lifting tank is driven to descend to the HF acid liquor tank; and (6) the nitrogen protection cover is opened, and the silicon wafers are taken out for checking. According to the method, the conical etching block is contacted with the cuts of the 8-inch wafers, so as to achieve the purpose of removing the oxidation films of the cuts. The device has the advantages of simple structure, convenience for operation, and low process cost.

Description

technical field [0001] The invention relates to a method and device for removing oxide film of 8-inch wafer incision Background technique [0002] With the rapid development of the domestic integrated circuit industry, the demand for silicon substrate materials is also increasing, and the quality requirements are becoming more and more stringent. It is usually necessary to carry out back sealing treatment on heavily doped silicon wafers, that is, grow a layer of SiO on the backside of the substrate wafer. 2 thin film due to impurities in SiO 2 The diffusion coefficient in silicon is much smaller than that in silicon, so impurities in the substrate can be effectively blocked. The ensuing problem is: growing SiO on the backside of the silicon wafer 2 At the same time as the film, SiO also grows on the edge of the silicon wafer 2 film, and this layer of SiO on the edge 2 The thin film will have a greater impact on the quality of the epitaxial layer on the front side of the...

AI Technical Summary

Problems solved by technology

The ensuing question is: the growth of SiO on the back of the silicon wafer 2 At the same time as the thin film, SiO is also grown on the edge of the silicon wafer. 2 thin film, while this layer of SiO at the edge 2 thin film, which will have a great impact on the quality of the epitaxial layer on the front side of the silicon wafer, so the edge oxide film must be removed

[0003] At present, the edge removal methods adopted in China mainly include film edge removal and roller edge removal. Film edge removal adopts the method of pasting PTFE blue film on the back of the silicon wafer to protect the oxide film on the back and remove the edge and incision oxide film. This process The cost of equipment and raw materials used is relatively high, and the production process is complex and difficult to operate

[0004] Roller defringing technology has been relatively perfect for back-sealing wafers below 6 inches. However, when the size of silicon wafers increases to 8 inches, the reference surface is replaced by incisions. The original roller defringing technology has encountered difficult problems. It is impossible to remove the kerf oxide film, so it is necessary to provide a new device for removing the kerf oxide film

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