The Fabrication of Photomixer by Mix-Match Lithography

• Main Authors: Ying-Lin Horng, 洪鶯玲
• Other Authors: Hsin-Fei Meng
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/85546662780819498105

碩士 === 國立交通大學 === 物理研究所 === 89 === The photomixer is a compact solid-state source that uses two single-frequency tunable diode lasers to generate a THz difference frequency by photoconductive mixing in low-temperature-grown GaAs (LTG-GaAs). We choose the self-complementary spiral antenna to be the photomixer because its high convertible efficiency, wide bandwidth, and frequency-independent. In this thesis, the mix-match lithography process technology is proposed to accomplish the photomixer. This technology is to mix optical lithography (OL) and electron beam lithography (EBL). It have the advantage of high resolution of EBL and high throughput of OL. Using OL to accomplish the big size patterns, like spiral antennas. Then, using EBL to directly writing the critical structure, like interdigitated electrode structures in the active region of antenna. The key of this process technology is to match and align the two layers. It is important to keep the process stable. We test OL and EBL process to find out the best process conditions or the process window. We successfully made 2-arm spiral antennas with interdigitated electrode structures of 0.7µm line-width and 1.3µm line-space in the 20μm×20μm active region of 7000µm antenna.