Method for evaluating wafer and method for manufacturing epitaxial wafer

Abstract

A method is provided which is capable of determining which of the deposition reaction and the etching reaction is causing wafer inner surface concave-convex portions with respect to the epitaxial reaction or the etching reaction on the outer surface of the wafer. A SOI wafer (S1) is prepared, and the thickness (S2) of the SOI layer of the SOI wafer was measured. The SOI wafer is turned upside downand placed on a pedestal so that the SOI layer faces the pedestal side, and the epitaxial reaction or the etching reaction (S3, S4) are performed. The SOI wafer after the reaction is inverted upsidedown so that the SOI layer is directed upward, and the thickness (S5, S6)of the SOI layer is measured. The in-plane distribution (S7) of the deposition reaction and the etching reaction on the inner surface of the wafer is obtained by determining the difference in thickness of the SOI layer before and after the reaction. Further, based on the obtained in-plane distribution, process conditions forepitaxial production for homogenizing the in-plane distribution are determined, and epitaxial growth is performed on the product substrate in accordance with the process conditions.

Description

technical field [0001] The present invention relates to a method of evaluating a reaction occurring on the inner surface of a wafer, which is accompanied by a deposition reaction (reaction of build-up deposition (film)) or an etching reaction on the outer surface of a wafer placed on a susceptor, and a method of manufacturing an epitaxial wafer And produced. Background technique [0002] With the high integration of semiconductor devices, the requirements for the quality of wafers constituting their raw materials have further increased. For epitaxial wafers, in addition to the flattening of the film thickness distribution of the epitaxial layer vapor grown on the outer surface, the smoothing of the unevenness of the inner surface (the wafer surface opposite to the side where the epitaxial layer is formed) is also a smoothness quality. One of the improved items. [0003] Since the reaction raw materials are usually not actively provided on the inner surface of the wafer, a ...

AI Technical Summary

Problems solved by technology

[0003] Since the reaction raw materials are usually not actively provided on the inner surface of the wafer, a huge reaction like that on the outer surface does not take place on the inner surface of the wafer, but only a slight deposition reaction and an etching reaction coexist, resulting in Concave and convex parts related to the design of the base

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