Variation reduction of a closed-loop precision ceramic micromachining process

This report details the investigation of the micromachining of a TiC.A1203 ceramic using a closed-loop lapping process. Currently the micromachining process laps a ceramic bar with only a priori flatness adjustment. Bar flatness is adjusted prior to the lap using optical measurement of lithography targets. The average value of a critical dimension determines lap completion. The critical dimension is determined with an embedded electronic lapping guide (ELG). The problem with this technique, as it is currently employed, is high product loss due to large variance of the critical dimension across the bar. A six microinch standard deviation is desired. Any product above or below specified critical dimension limits are scrapped, so the variance reduction directly impacts immediate and downstream process yields. An alternative approach is proposed using electrostrictive actuators in a closed control loop to deform the bar during lap processing. The closed-loop lapping (CLL) process significantly decreases critical dimension process variance.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Materials Science and Engineering

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

1996

Author dc:creator

• Fanger, David J. (David James)

Advisor dc:contributor.advisor

• James M. Utterback and Michael J. Cima.

• Sloan School of Management
• Materials Science and Engineering

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/41429

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/41429