A monolithic 48-stage Si-micromachined Knudsen pump for high compression ratios

Author

Gupta, N.K. ; An, S. ; Gianchandani, Y.B.

Author_Institution

Univ. of Michigan, Ann Arbor, MI, USA

fYear

2012

fDate

Jan. 29 2012-Feb. 2 2012

Firstpage

152

Lastpage

155

Abstract

This paper describes a microchip of 10.35×11.45 mm² footprint that can self-evacuate on-chip cavities from 760 Torr to <;50 Torr or from 250 Torr to ≈5 Torr. The power consumed is ≈1,350 mW. These compression ratios of 15 and 50 offer >;10× improvement above those previously reported. The microfabrication process utilizes a single silicon substrate and requires five masks. A process is described for hermetic sealing of plasma enhanced chemical vapor deposited (PECVD) oxide/nitride layers using atomic layer deposited (ALD) Al₂O₃.

Keywords

atomic layer deposition; elemental semiconductors; hermetic seals; masks; micromachining; micropumps; plasma CVD; silicon; Si; atomic layer deposition; compression ratios; hermetic sealing; masks; microchip; microfabrication process; monolithic micromachined Knudsen pump; oxide-nitride layers; plasma enhanced chemical vapor deposition; single silicon substrate; Cavity resonators; Creep; Heat pumps; Micropumps; Silicon; Substrates; Thermal conductivity; Knudsen pump; Pirani gauge; Poiseuille flow; compression ratio; sealing; thermal creep flow; thermal transpiration;

fLanguage

English

Publisher

ieee

Conference_Titel

Micro Electro Mechanical Systems (MEMS), 2012 IEEE 25th International Conference on

Conference_Location

Paris

ISSN

1084-6999

Print_ISBN

978-1-4673-0324-8

Type

conf

DOI

10.1109/MEMSYS.2012.6170116

Filename

6170116