Physical Sensors & Devices

Research that includes:

  • Silicon MEMS actuators: comb, electro-thermal, and plastic deformation
  • Precision electronic sensing and measurements of capacitive, frequency, and coulombic MEMS variables
  • Structures and architectures for gyroscopes, accelerometers, micro strain gauges for direct application to rigid structures e.g., steel, and levitated MEMS

BEB22: A Sub-mW Mode Matching Sigma-Delta Vibratory Gyroscope Readout Circuit

Chinwuba D. Ezekwe

We present the design and experimental results of a low-power, high-resolution gyroscope readout circuit. Several techniques are combined to enable an unprecedented level of power savings. Chief among them are automatic mode-matching, positive position sigma-delta force-feedback, and current integrator based position sensing. Mode-matching relaxes the electronic noise budget of the front-end amplifier by the sense Q, resulting in a proportional reduction in front-end power dissipation. Unfortunately, it also results in an extremely narrow open-loop sensor bandwidth owing to the high...

DL13: Multidirectional Force and Torque Sensor for Insect Flight Research

Mansoor Nasir

In order to understand the unsteady aerodynamics of insect flight, a sensor has been fabricated that measures the small multidirectional forces generated by fruit flies during tethered flight while simultaneously supporting it inside a LED flight simulator arena. This sensor will provide quantitative data that will help to better understand sensorimotor mechanisms of flight control in flying insects.

Project end date: 01/29/08

BPN443: Ultra-Smooth Conducting Parallel Plates with Nanoscale Separation for Single Molecule Sensing and Investigation of Casimir Force

Aaron M. Katzenmeyer

We constructed a pair of parallel conducting metal (Ag) plates separated by patterned molecular monolayers at the corners of the plates. A special metal deposition process was developed to ensure atomic scale flatness in the conducting plates. The separation between the plates can be controllably varied between several angstroms and tens of nanometers by varying the length of the molecules and/or employing conventional substrate processing techniques. The structure is an efficient sensor for detecting single molecules via surface enhanced Raman spectroscopy (SERS). The unique...

APP78: SiC TAPS: Capacitive Sensors Design and Fabrication

Babak Jamshidi

The main objective of the project is to design and fabricate capacitive sensors capable of performing under harsh environments. The main focus of the project is to develop a strain gauge which measures strain at micron scale to improve the operational characteristics of its substrates in applications such as automotive and aerospace. Contrary to traditional and commercial strain gauges, temperature and aging have a relatively small influence on the sensitivity and precision of this type of sensor. Three major goals have been set for the course of research. The most prior goal is to...

BPN372: SiC TAPS: Strain Gauge System Design

David Myers

The SiC MEMS strain gage can be oriented and placed on round tubing such that it can be utilized as a torque measurement device. To this extent, a shear strain application system has been designed and is currently being constructed. This device utilizes a common automotive halfshaft, a component which would see fairly high torques during its lifetime and could benefit from torque monitoring systems. Validation of the strain application system has been completed, and strain gauge device testing is commencing. The testing will focus on characterizing strain transfer and strain gauge...

BPN432: Micromechanical Resonant Displacement Gain Stages

Bongsang Kim

This overall project aims to apply mechanical displacement amplification for MEMS resonators to improve the performance of various analog and digital signal processors in RF MEMS devices. These performance benefits will be investigated by analytical models and numerical simulations as well as fabrication and experimental verification.

Project end date: 01/29/10

BPN483: High Z Materials for Nuclear Detection

Mitchell H. Kline
Igor I. Izyumin

Homeland security requires development of cost-effective nuclear detection capability to distinguish threats from non- threats. High atomic number (Z) semiconductor devices with high efficiency, sufficient energy resolution, and room temperature operation offer the potential to meet this objective rapidly, reliably, and inexpensively, but have been challenging to realize, despite significant efforts spanning 30 years. To achieve this important goal, there is strong consensus that fundamental limitations on charge collection in high Z materials must be understood, material quality...

BPN386: CMOS-Integrated Nanowire-Based Molecular and Gas Sensors

Karl Skucha

This project first aims to develop a process flow to integrate silicon nanowires onto a CMOS substrate, both via and top-down and bottom-up processes. Then, by carefully designing the underlying circuitry and functionalizing the nanowire transducers, we hope to demonstrate a fully functional integrated sensing platform for various molecular agents and/or gases. The overall goal and application is to create an easy-to-use CMOS-based sensing system for low-cost portable applications.

Project end date: 02/04/10

BPN357: Parametrically-Amplified MEMS Magnetometer

Matthew J. Thompson

The focus of this project is on developing parametric MEMS resonators for application to gyroscopes, magnetometers, and RF MEMS filters. Optical parametric oscillators and microwave parametric amplifiers are widely utilized but their current MEMS counterparts are largely an academic curiosity. Parametric MEMS resonators have a number of advantages over the current state-of-the-art in MEMS resonator technology. First, they allow direct mechanical amplification of the sensor input, reducing the requirement for electronic amplification and allowing a corresponding reduction in power...

BPN418: MEMS Poly/Nano: Polymer Coated Cantilevers for Infrared Heat Sensing

Clinton G. Warren

A polymer-polysilicon cantilever bimorph device is to be utilized as a thermal infrared detector. Third generation prototypes were designed, fabricated, and are being tested. These device utilize a capacitive readout scheme, a double-beam design in order to eliminate the effect of residual stress in the polymer layer, and a nitride stopper layer for reduced sticking and pull-in. Devices are characterized using optical and thermal methods. Future goals include detailed characterization of the current prototypes, analytical model correlation, low-pressure testing, geometric...