Abstract
We describe the design, fabrication, and characterization of arrays of uncooled infrared and terahertz micromechanical detectors that utilize SiO2 as a main structural material. Materials with highly dissimilar coefficients of thermal expansion, namely, Al and SiO2, were used to form folded bimaterial regions. This approach improved the detector sensitivity by 12 times compared to SiNx -based detectors of similar shape and size. Two types of structural SiO2 layers were investigated: thermally grown and plasma-enhanced chemical-vapor-deposited SiO2. Fabrication of the detector arrays relied on a straightforward process flow that involved three photolithography steps and no wet etching. The noise equivalent temperature difference intrinsic to the detectors fabricated during this work can reach 3.8 mK when excluding any contribution from the optical readout used to interrogate the arrays.
Original language | English |
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Article number | 054508 |
Journal | Journal of Applied Physics |
Volume | 104 |
Issue number | 5 |
DOIs | |
State | Published - 2008 |
Externally published | Yes |
Funding
This work was supported by a grant from the Office of Naval Research and by the LDRD program at Oak Ridge National Laboratory. This work was performed in part at the Cornell NanoScale Facility, a member of the National Nanotechnology Infrastructure Network, which is supported by the National Science Foundation (Grant No. ECS-0335765). The authors would like to thank the CNF staff for their valuable help and advice on microfabrication process, as well as Dr. Alvin J. Sanders for providing helpful advice. Oak Ridge National Laboratory is operated for the U.S. Department of Energy by UT-Battelle under Contract No. DE-AC05-00OR22725.