Graduation Year


Document Type




Degree Granting Department

Electrical Engineering

Major Professor

Shekhar Bhansali, Ph.D.

Co-Major Professor

Scott Samson, Ph.D.

Committee Member

Weidong Wang, Ph.D.


Thermal actuator, Polymumps, Anodic bonding, Gear, Pirl


This thesis presents the design and fabrication of a re-configurable micromirror array which can be used as a component of an optical microspectrometer. In an optical microspectrometer, an array of mechanically positionable micromirrors can be implemented as a reconfigurable exit slit to selectively focus particular wavelengths of a diffracted spectrum onto the detector stage. The signal to noise ratio and response time of an optical microspectrometer can be vastly improved by this technique.

In the approach presented here, a hybrid bulk- and surface- micromachining process is demonstrated for fabrication of a 1XN array of micromirrors. The reconfigurable micromirrors presented here comprise of two elements, a surfacemicromachined positioning mechanism, and a bulk-micromachined mirror. These elements are finally integrated using a flip-chip bonding technique.

The integrated micromirror assembly can be positioned by means of a driving mechanism consisting of arrayed electrothermal actuators. Various techniques for fabricating the micromirror array components are discussed in detail in this thesis along with a review of techniques applicable for integrating the individual components.

In order to enhance the efficiency of the positioning system, the classic electrothermal actuators were redesigned in this research. The modified design of thermal actuators is introduced in this thesis. An analysis of the modified thermal actuators is also presented to demonstrate the validity of the suggested modifications.