Integrated a-Si:B Microbolometer Arrays Based on Improved Porous Silicon Micromachining Techniques

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2006,（5）
• 页码范围: 1331-1334
• 页数: 4页
• 语种: 英文

摘要

A monolithic uncooled 8 × 8 microbolometer array with boron-doped a-Si (a-Si:B) thermistors as active elements is presented. The a-Si:B film was deposited by plasma enhanced chemical vapour deposition. To decrease the thermal conductance of the microbolometer, a-Si:B thermistor was formed on a four-leg suspended microbridge.The improved porous silicon micromachining techniques described here enable the integration of the sensor array with the metal-oxide-semiconductor readout circuitry. The sacrificial material of porous silicon is prepared in the first step. It is then well protected all the time during the fabrication of metal-oxide-semiconductor field effect transistors and microbolometers before being released. Measurements and calculations show that the uncorrected uniformity of the 8 × 8 microbolometer array is about 4.5%, and the detectivity of2.17 × 10scm Hz1/2W-1 is achieved at a chopping frequency of 30 Hz and a bias voltage of 5 V with a thermal response time of 12.4 ms.