Formation method of semiconductor structure

Abstract

The invention discloses a semiconductor structure forming method, and the method comprises the steps: forming a substrate, and forming a first material layer, a second material layer and a third material layer on the substrate, wherein the second material layer covers at least a part of the surface of the substrate and the surface of a side wall of the first material layer, and the third material layer is aligned with the surface of the first material layer; forming a mask layer with a first opening which is exposed out of the surface of the first material layer and a part, covering the side wall of the first material layer, of the surface of the second material layer; etching the first and second material layers at certain thickness along the first opening, wherein the etching rate of the second material layer is greater than the etching rate of the first material layer; etching the mask layer, and forming a second opening, wherein the second opening enables the remaining part of the first material layer and the part, located on the surface of the side wall of the first material layer, of the second material layer to be completely exposed; carrying out the etching of the remaining parts of the first and second material layers along the second opening till the surface of the substrate, and forming a groove, wherein the side walls, located at two sides of the groove, of the third and second material layers are aligned with each other. The method can improve the performance of a formed semiconductor structure.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a method for forming a semiconductor structure. Background technique [0002] Micro-Electro-Mechanical System (MEMS, Micro-Electro-Mechanical System) is an advanced manufacturing technology platform. It is developed on the basis of semiconductor manufacturing technology. MEMS technology uses a series of existing technologies and materials such as lithography, corrosion, and thin film in semiconductor technology. With the continuous development of semiconductor technology, micro-electromechanical systems have also developed rapidly. [0003] Due to its high integration and stable performance, MEMS oscillators have been widely developed and applied. [0004] In the process of forming a MEMS oscillator, it is formed as figure 1 The semiconductor structure described. [0005] Please refer to figure 1 , the semiconductor structure includes: a substrate 10, a first material...

AI Technical Summary

Problems solved by technology

In the prior art, during the etching process, the etching rate of the second material layer 22 is greater than the etching rate of the first material layer 21, so it is easy to over-etch the second material layer 22 below the third material layer 23 , so that part of the third material layer 23 is suspended, causing the third material layer 23 to collapse easily

In the subsequent cleaning process, further corrosion will be caused to the second material layer 22 below the third material layer 23, so that problems such as peeling of the third material layer 23 will occur, which will affect the final MEMS oscillator. performance

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