Integrated mold/surface-micromachining process
Abstract
We detail a new monolithically integrated silicon mold/surface-micromachining process which makes possible the fabrication of stiff, high-aspect-ratio micromachined structures integrated with finely detailed, compliant structures. An important example, which we use here as our process demonstration vehicle, is that of an accelerometer with a large proof mass and compliant suspension. The proof mass is formed by etching a mold into the silicon substrate, lining the mold with oxide, filling it with mechanical polysilicon, and then planarizing back to the level of the substrate. The resulting molded structure is recessed into the substrate, forming a planar surface ideal for subsequent processing. We then add surface-micromachined springs and sense contacts. The principal advantage of this new monolithically integrated mold/surface-micromachining process is that it decouples the design of the different sections of the device: In the case of a sensitive accelerometer, it allows us to optimize independently the proof mass, which needs to be as large, stiff, and heavy as possible, and the suspension, which needs to be as delicate and compliant as possible. The fact that the high-aspect-ratio section of the device is embedded in the substrate enables the monolithic integration of high-aspect-ratio parts with surface-micromachined mechanical parts, and, in the future,more »
- Authors:
- Publication Date:
- Research Org.:
- Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
- Sponsoring Org.:
- USDOE, Washington, DC (United States)
- OSTI Identifier:
- 215318
- Report Number(s):
- SAND-96-0401C; CONF-960268-4
ON: DE96006470
- DOE Contract Number:
- AC04-94AL85000
- Resource Type:
- Conference
- Resource Relation:
- Conference: Society of Photo-Optical Instrumentation Engineers (SPIE) smart structures and materials conference, San Diego, CA (United States), 26-29 Feb 1996; Other Information: PBD: [1996]
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; 36 MATERIALS SCIENCE; INTEGRATED CIRCUITS; MACHINING; SURFACE FINISHING; ACCELEROMETERS; SILICON; SIZE; ETCHING; POLISHING; MOLDING
Citation Formats
Barron, C C, Fleming, J G, Montague, S, Sniegowski, J J, and Hetherington, D L. Integrated mold/surface-micromachining process. United States: N. p., 1996.
Web.
Barron, C C, Fleming, J G, Montague, S, Sniegowski, J J, & Hetherington, D L. Integrated mold/surface-micromachining process. United States.
Barron, C C, Fleming, J G, Montague, S, Sniegowski, J J, and Hetherington, D L. 1996.
"Integrated mold/surface-micromachining process". United States. https://www.osti.gov/servlets/purl/215318.
@article{osti_215318,
title = {Integrated mold/surface-micromachining process},
author = {Barron, C C and Fleming, J G and Montague, S and Sniegowski, J J and Hetherington, D L},
abstractNote = {We detail a new monolithically integrated silicon mold/surface-micromachining process which makes possible the fabrication of stiff, high-aspect-ratio micromachined structures integrated with finely detailed, compliant structures. An important example, which we use here as our process demonstration vehicle, is that of an accelerometer with a large proof mass and compliant suspension. The proof mass is formed by etching a mold into the silicon substrate, lining the mold with oxide, filling it with mechanical polysilicon, and then planarizing back to the level of the substrate. The resulting molded structure is recessed into the substrate, forming a planar surface ideal for subsequent processing. We then add surface-micromachined springs and sense contacts. The principal advantage of this new monolithically integrated mold/surface-micromachining process is that it decouples the design of the different sections of the device: In the case of a sensitive accelerometer, it allows us to optimize independently the proof mass, which needs to be as large, stiff, and heavy as possible, and the suspension, which needs to be as delicate and compliant as possible. The fact that the high-aspect-ratio section of the device is embedded in the substrate enables the monolithic integration of high-aspect-ratio parts with surface-micromachined mechanical parts, and, in the future, also electronics. We anticipate that such an integrated mold/surface micromachining/electronics process will offer versatile high-aspect-ratio micromachined structures that can be batch-fabricated and monolithically integrated into complex microelectromechanical systems.},
doi = {},
url = {https://www.osti.gov/biblio/215318},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Mar 01 00:00:00 EST 1996},
month = {Fri Mar 01 00:00:00 EST 1996}
}