Title :
Bias dependent etching of polysilicon mixed monocrystalline-polycrystalline silicon structures
Author :
Riou, J.C. ; Spirkovitch, S. ; Sangouard, P. ; Baillieu, B.
Author_Institution :
Schlumberger, Melun, France
Abstract :
An etching process developed for the realization of polysilicon structures using the standard CMOS process is described. Thin polysilicon beams have been fabricated using this technique. Electrochemical investigations give two important results: no anisotropic effects were observed and heavily doped polysilicon gives an OFP (oxide formation potential) of the same order as those of single-crystal silicon. A standard IC process flow and a PN junction etch-stop to suppress the clamping area step in order to realize a double-compensated structure was studied. These results demonstrate a new type of sacrificial layer that produces no damage to an SiO2 layer. Poly-Si chemical properties in KOH aqueous solutions were also studied
Keywords :
CMOS integrated circuits; elemental semiconductors; etching; micromechanical devices; silicon; CMOS process; KOH-H2O solution; Si; Si-SiO2; bias dependent etching; chemical properties; clamping area step; elemental semiconductor; etch-stop; etching process; micromachining; mixed monocrystalline-polycrystalline; oxide formation potential; polysilicon structures; sacrificial layer; CMOS integrated circuits; CMOS technology; Contacts; Crystalline materials; Etching; Hafnium; Integrated circuit noise; MONOS devices; Mechanical factors; Silicon compounds;
Conference_Titel :
Micro Electro Mechanical Systems, 1992, MEMS '92, Proceedings. An Investigation of Micro Structures, Sensors, Actuators, Machines and Robot. IEEE
Conference_Location :
Travemunde
Print_ISBN :
0-7803-0497-7
DOI :
10.1109/MEMSYS.1992.187694
