Electrical & Computer Engineering     |     Carnegie Mellon

Wednesday, January 29, 12:00-1:00 p.m. HH-1112


Nilmoni Deb
Carnegie Mellon University
Built-in Self Test for Symmetric Microelectromechanical Systems (MEMS)

Microelectromechanical systems (MEMS) are making steady inroads into various applications that include automotives, aeronautics, navigation, fluidics, etc. The manufacturing test of MEMS is a challenge due to their multi-domain nature. Our research is focused on developing and improving test methods to increase reliability and reduce escape of defective devices. Built-in self-test (BIST) techniques that improve testability are urgently needed since they alone can be used to test the device during its operational life. In this presentation, we describe a built-in self-test technique for MEMS that is applicable to symmetrical micro-structures. A combination of existing layout features and additional circuitry is used to make measurements from symmetrically-located points. In addition to the normal sense output, self-test outputs are used to detect the presence of layout asymmetry that are caused by local, hard-to-detect defects. Simulation results for an accelerometer reveal that our self-test approach is capable of distinguishing misbehavior resulting from local defects and manufacturing process variations. The advantage of our BIST technique over current approaches used by industry is that it can be used during manufacturing test as well; an important feature that can potentially expose certain hard-to-detects that would normally escape to the customer.Bio
Nilmoni Deb received his B.Tech (Hons) degree from Indian Institute of Technology, Kharagpur, India, in 1997 and MS in Electrical and Computer Engineering from Carnegie Mellon University, Pittsburgh, USA, in 1999. Currently he is a Ph.D. student in the Department of ECE, Carnegie Mellon University, Pittsburgh, USA, with broad research interests in Test for MicroElectroMechanical Systems.