Deep hole silicon etching method

Abstract

The invention provides a deep hole silicon etching method, which belongs to the semiconductor manufacture technical field. The method comprises an etching step and a side wall protective layer deposition step which are alternately carried out, the etching step is capable of supplying etching reaction gas to a reaction chamber used for putting the silicon chip to be etched, a silicon layer is etched to form an opening, the side wall protective step is capable of supplying sidewall protection gas, wherein the sidewall protection gas comprises siliceous gas and oxygen-containing gas, a silicon oxide layer is formed at the sidewall and the bottom of the opening. The deep hold sidewall etched by the method of the invention has higher intensity without extra reinforcement step, so that the etching efficiency of entirety is increased.

Description

technical field [0001] The invention belongs to the technical field of semiconductor manufacturing, and in particular relates to a through silicon Via (TSV) etching technology, in particular to a method for forming a sidewall protective layer in deep hole silicon etching. Background technique [0002] In the field of semiconductor manufacturing technology, in fields such as MEMS (Micro-Electro-Mechanical Systems, micro-electro-mechanical systems) and 3D packaging technology, it is usually necessary to etch deep via holes in materials such as silicon. For example, in bulk silicon etching technology, deep through-silicon vias (Through-Silicon-Via, TSV) have a depth of hundreds of microns and an aspect ratio much greater than 10, and deep reactive ion etching is usually used to etch the bulk silicon formed. [0003] figure 1 Shown is a schematic diagram of the deep reactive ion etching method in the prior art. In the prior art, the deep reactive ion etching of TSV is usually...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to avoid the problem that the smoothness of the side wall of the through hole is reduced and the etching efficiency is reduced during the etching process of the deep expensive through hole.

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