- 學位論文
CMOS-MEMS微型加熱板應用於一氧化碳感測器之研究
The research of CMOS-MEMS Micro-hotplate applied to carbon monoxide sensors
摘要
本文提出完全與CMOS(complementary metal oxide semiconductor, CMOS)製程相符的微加熱器(micro-hotplate)，其利用氣體乾蝕刻法，將矽基板做非等向性蝕刻，可結合於一氧化碳(carbon monoxide, CO)感測器的應用元件。此微加熱器與未蝕刻矽基板之微加熱器(non-etching one)相比，在相同功率損耗下，可提供相對較高之操作溫度，以提供感測器在感測時所需之操作溫度。另一方面，500 nm的氣體感測材料二氧化錫(tin oxide)薄膜成功地以射頻濺鍍(r.f. sputter)法，沉積於指叉狀(interdigited electrode)電極上。最後，以不同濃度的一氧化碳氣體來測試其響應(response)特性，結果顯示其在短時間內(150 sec)即有明顯之響應表現，最高之靈敏度為16.51 %。此晶片利用TSMC 0.35 μm 2P4M CMOS 標準製程製作，並結合後CMOS (post-CMOS)體型微加工技術(bulk micromachining)，來將感測晶片作為薄膜式元件，初步證實其可用於有毒性氣體(toxic gas) CO的偵測。
並列摘要
This thesis presents the process of fully CMOS(complementary metal oxide semiconductor)-compatible with microhotplate, it apply gas-dry-etching on silicon substrate for anisotropic etching and intergrated on carbon monoxide(CO) sensor. Compare to the microhotplate and non-etching silicon substrate one, this microhotplate provided higher operating temperature under same ratio of power consumption, so the sensor could had higher temperature and cost lower power consumption while working. On the other hand, the 500 nm of tin oxide’s thin film (SnO2) of gas-sensing material were deposited successfully on the interdigited electrode by r.f. sputtering. Last, by different concentration of CO to measure its response characteristic, the result showed that in a short time period (150 sec), it had clear responding. This chip has been fabricated in industrial 0.35 μm CMOS technology and combined bulk micromachining of post-CMOS technologies to form the membrane –type device; this could prove that it could be applied on detecting of toxic gas.