Bulk silicon machining process based on silicon chip etching and puncturing

Abstract

The invention discloses a bulk silicon machining process based on silicon chip etching and puncturing, which comprises the following steps of preparing a patterned photoresist mask on the surface of a silicon chip; putting a metal film on the back surface of the silicon chip; adhering the metal film to a supporting chip by using vacuum oil, wherein the supporting chip is a silicon chip with an oxide layer on the surface; etching and puncturing the silicon chip to obtain a bulk silicon microstructure by using an inductively coupled plasma dry-etching system, wherein a staged etching method is adopted for inductive coupled plasma dry-etching, and comprises a plurality of etching stages each of which is alternately and cyclically implemented by three steps of passivation, bombardment and etching in an inductive coupled plasma machine, and along with the increasing of the etching depth, the bombardment intensity of the bombardment step in each etching stage is gradually enhanced; removing the photoresist mask and the metal film, and releasing the bulk silicon microstructure. According to the process, the selection ratio of photoresist, the etching depth and the perpendicularity of the sidewall of an etching groove can be effectively increased.

Description

technical field [0001] The invention belongs to the technical field of microelectronic device processing, and more specifically relates to a bulk silicon processing technology based on silicon slice punching. Background technique [0002] Micro-Electro-Mechanical Systems (MEMS) is a high-tech field developed in recent decades, and MEMS technology based on microelectronic technology has developed particularly rapidly. From the initial surface processing technology to the bulk processing technology, with the development of miniaturization and integration, the deep silicon etching process has become a key process in the manufacturing technology of microelectronic devices. The basic idea of ​​deep silicon etching is the alternating process of reactive ion etching and surface passivation, and the purpose of anisotropic etching is achieved by alternately feeding etching gas and passivating gas. Using this technology can obtain a large aspect ratio and a steep sidewall etching res...

AI Technical Summary

Problems solved by technology

However, limited by the process conditions at this stage, the etch depth of bulk processing generally stays at a shallow stage relative to the thickness of the silicon wafer. When the depth is large, it is difficult to process, and it is difficult to obtain good sidewall roughness and vertical thickness. Spend

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