Fabrication of Grating Structures with Periods Less Than 0.5 μm on SOI(110) Wafers Using Scanning Probe Lithography

• Main Authors: Chih-hung Chen, 陳志宏
• Other Authors: Tzong-Yow Tsai
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/25728258512109143702

碩士 === 國立成功大學 === 微電子工程研究所碩博士班 === 97 === The purpose of the study is to fabricate grating period less than 0.5 μm using Scanning Probe lithography. The thesis is organized with three parts. First, the efficiencies of lithography oxidation were measured and discussed using various DC voltages, AC frequencies and oxidation scanning rates. Second, TMAH 25 % wt. solution was employed in anisotropic wet etching, and the etched grating shapes and etching rates were evaludated under different temperatures. Third, with low humidity, the oxidation width were further decreased by modifying the distance from the AFM nano-probe to the wafer surface. By experiment, the environment parameters of optimization were obtained as: DC voltage 10 V, scanning probe rate 1 μm/s, Z(T:B) at -0.9 V and environment humidity 39 %. Grating structure of the period of 0.5 μm, structure depth of 194.8nm and structure width of 195 nm was achieved by 60-second wet etching in TMAH at 60℃. These parameters of optimization could provide good references for further research in patterning grating structure on the top surface of a SOI waveguide.