Hydrogen peroxide etching and stability of p-type poly-SiGe films

Author

Bircumshaw, B.L. ; Wasilik, M.L. ; Kim, E.B. ; Su, Y.R. ; Takeuchi, H. ; Low, C.W. ; Liu, G. ; Pisano, A.P. ; King, T.J. ; Howe, R.T.

Author_Institution

Dept. of Mech. Eng., California Univ., Berkeley, CA, USA

fYear

2004

fDate

2004

Firstpage

514

Lastpage

519

Abstract

In this paper, a model is developed for the etching of as-deposited, in-situ, boron-doped, LPCVD poly-SiGe films in hydrogen peroxide. The model is corroborated by etching results for poly-SiGe alloys with Ge content between 55 and 70%. The results indicate that Ge content in the 55 to 65% range is desirable for maintaining high selectivity with respect to poly-Ge sacrificial layers in a peroxide etch while attaining a polycrystalline film structure (at about 425°C, 50% Ge content poly-SiGe films are amorphous). The drift in residual stress of poly-SiGe films at room temperature in dry and wet ambients is also reported. Finally, the etching of in-situ, boron-doped, LPCVD poly-Ge films in hydrogen peroxide is studied.

Keywords

CVD coatings; Ge-Si alloys; boron; etching; hydrogen compounds; internal stresses; semiconductor materials; semiconductor thin films; 293 to 298 K; H₂O₂; SiGe:B; boron doped LPCVD poly-Ge films; hydrogen peroxide etching; low pressure chemical vapour deposition; p-type polySiGe films; polycrystalline film structure; residual stress; room temperature; stability; Erbium; Etching; Fabrication; Germanium alloys; Mechanical engineering; Mechanical sensors; Micromechanical devices; Radio frequency; Stability; Temperature;

fLanguage

English

Publisher

ieee

Conference_Titel

Micro Electro Mechanical Systems, 2004. 17th IEEE International Conference on. (MEMS)

Print_ISBN

0-7803-8265-X

Type

conf

DOI

10.1109/MEMS.2004.1290635

Filename

1290635