Formation method of zero object

Abstract

The invention discloses a formation method of a zero object, which is used for the epitaxial technology containing a buried layer graph. The formation method comprises the following steps: 1) oxidizing and forming a cushion oxide layer on the surface of a substrate; 2) defining the position of the buried layer graph and the zero scale graph on the substrate by a photoetching mask simultaneously containing the buried layer graph and the zero scale graph and the photoetching technology; 3) taking photoresist formed by the photoetching technology as the mask, carrying out ion implantation, and respectively forming the buried layer and the ion implantation area on the buried layer graph position and the zero scale graph position; 4) removing the photoresist and the cushion oxide layer by common technology; 5) carrying out heat treatment under oxygen-rich environment to oxidize the surface of the substrate, and boosting the buried layer; and 6) removing the oxide layer formed on the surface of the substrate in step 5) with the wet method to obtain the structure with the zero object graph and the buried layer graph. The method of the invention simplifies the formation technology of the zero object.

Description

technical field [0001] The invention relates to a method for forming a zero mark, in particular to a method for forming a zero mark in an epitaxy process including buried layer patterns. Background technique [0002] The buried layer is usually used in the epitaxial process to reduce the contact resistance, and the zero mark is the pattern formed on the silicon wafer for the first time, which is used for the next photolithographic alignment. For the epitaxial process with buried layer pattern, the formation of zero mark is usually before the formation of buried layer pattern. A specific example can be found in Figure 1a to Figure 1e : A silicon oxide substrate forms a pad oxide layer on its surface, defines a zero mark pattern with a photoresist on the silicon substrate 1 through a photolithography process, and then uses the photoresist 2 as a mask to etch the silicon substrate to form a zero mark Mark 6, and then remove the photoresist 2; then use another photolithography...

AI Technical Summary

Problems solved by technology

The above-mentioned formation process is relatively cumbersome, requiring a two-step photolithography process and two photolithography masks

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