Inverted trapezoidal groove etching process method

Abstract

The invention discloses an inverted trapezoidal groove etching process method, and belongs to the field of microelectronic manufacturing processes. The invention relates to an inverted trapezoidal groove etching process method, which comprises the following steps: 1) oxidizing a silicon substrate material to form an oxide layer, coating a photoresist on the oxide layer, and photoetching accordingto a design layout; 2) removing the oxide layer in the photoetching region by adopting an RIE etching method until the silicon substrate is exposed; (3) etching the silicon substrate step by step by adopting an inductively coupled plasma etching machine, alternately etching by adopting C4F8 and SF6, and obtaining a silicon groove with a preset depth after etching is completed; etching the silicongroove by adopting SF6 and O2 etching methods, and obtaining an inverted trapezoidal silicon groove after etching is completed; and 4) after the etching is finished, removing the photoresist and the oxide layer by adopting a wet method to obtain the silicon device. According to the process method disclosed by the invention, the inverted trapezoidal grooves with different silicon groove depths canbe obtained, and different process requirements are met.

Description

technical field [0001] The invention belongs to the field of microelectronics manufacturing technology, and specifically relates to an etching method of an inverted ladder groove. Background technique [0002] At present, SF is generally used for dry etching silicon grooves of silicon substrate materials 6 The etching method combined with chlorine base, the etching depth is generally shallower within 2um; however, using C 4 f 8 and SF 6 The deep silicon groove obtained by the alternate etching method cannot form the shape of the inverted trapezoidal groove, which cannot meet the actual process requirements. Contents of the invention [0003] The purpose of the present invention is to provide an inverted ladder groove etching process method, which can effectively solve the current problem of inverted ladder shape formation in silicon groove etching. [0004] In order to achieve the above object, the present invention adopts the following technical solutions to achieve: ...

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Problems solved by technology

[0002] At present, SF is generally used for dry etching silicon grooves of silicon substrate materials 6 The etching method combined with chlorine base, the etching depth is generally shallower within 2um; however, using C 4 f 8 and SF 6 The deep silicon groove obtained by the alternate etching method cannot form the shape of the inverted trapezoidal groove, which cannot meet the actual process requirements

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