Silicon Corrosion during Selective Silicon Nitride Etch with Hot Diluted Hydrofluoric Acid-Reference-Cited by-同舟云学术

Silicon Corrosion during Selective Silicon Nitride Etch with Hot Diluted Hydrofluoric Acid

Published:2021-02 Issue: Volume:314 Page:107-112
ISSN:1662-9779
Container-title:Solid State Phenomena
language:
Short-container-title:SSP

Author:

Garnier Philippe¹,Massin Thomas¹,Chatelet Corentin¹,Oghdayan Emmanuel¹,Lauerhaas Jeffrey²,Morote Carlos²,Butterbaugh Jeffery W.³

Affiliation:

1. STMicroelectronics

2. TEL Manufacturing and Engineering of America, Inc.

3. FSI International Inc.

Abstract

Silicon nitride is commonly etched by hot orthophosphoric acid. Hot diluted hydrofluoric acid is hereby used as an alternative. Nonetheless, in presence of silicon surfaces, some corrosion has been evidenced, degrading significantly active areas during the STI (Shallow Trench isolation) integration. Oxygen in hot deionized water or hot HF generates this corrosion and selecting a relevant chemical oxide before dispensing hot diluted HF is key in solving the concern.

Publisher

Trans Tech Publications, Ltd.

Subject

Condensed Matter Physics,General Materials Science,Atomic and Molecular Physics, and Optics

Link

https://www.scientific.net/SSP.314.107.pdf

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