由於近年來早產兒的的快速增加，根據統計每年在台灣的新生兒中大約有7%是早產兒。由於早產兒的器官發育大都尚未完成，加上早產兒的成長速度相當緩慢，因此如何讓早產兒成長速度加快是一個重要的課題；因此，能夠利用非侵入式並且快速地提供醫護人員判斷其成長狀態的儀器將是首要完成的任務，其中間接熱量計來量測早產兒的能量消耗狀況是一個方法，然而由於傳統的間接熱量計的體積較大而且價錢昂貴，使得無法普遍地應用在臨床及家庭照護上，為了改善這些問題，將感測器微小化並結合積體電路設計技術將量測系統整合成微小的晶片將是一個解決的方法，本論文提出以多個微小型感測器及無線發射模組組合成的微小型能量量測系統為基礎的架構，並且以矽晶元為基材在配合微機電技術設計出微型氧氣感測器；其能夠在150C的溫度下量測氧氣濃度(21%-50%)，並且針對不同結構的微型加熱器；包括薄膜型、薄膜加薄矽型、懸橋加薄矽型三種作分析，另外在180C的溫度下，流量感測器在0-10 m/sec的流速下有線性的輸出。除此之外，為了更有效率的量測氧氣濃度，本論文提出一個自動化氧氣量測及校正系統針對其中的氧氣量測部分作探討，藉由網際網路的遠端遙控來監控氧氣感測器的量測環境、測試條件、方法及擷取量測的資料，可以更正確且又有效率的提供研究人員完成氧氣感測器特性的量測。

Although the conventional indirect calorimeter is a valuable tool, its size and expense prohibits its widespread use in hospitals. Furthermore, its flow-through measurement technique dilutes the respiratory variations, and hence high-precision detection instrumentation is required. These limitations may be overcome by combining MEMS with CMOS circuit design technology to develop an innovative SOC biochip as the basis of a miniaturized energy consumption measurement system. Typically, the system is designed to operate with higher oxygen concentrations. Accordingly, the current thesis deals with the development of mircromachined oxygen sensors capable of sensing higher concentrations of oxygen at a lower operation temperature of 150C. The proposed gas sensors consist of a polysilicon resistor and a sensing metal-oxide film placed on a thermally isolated silicon-nitride membrane or bridge. The sensing film is a tin-oxide sheet, which has been doped with a low concentration of 2wt% Li.
This thesis involves the development of three different types of oxygen sensors, which are distinguished from each other by the structure of their micro-heaters. The first type is a micro-heater on a silicon nitride membrane, the second type employs a membrane located on a thin silicon layer, and the third type uses a bridge membrane with a thin underlying layer of silicon. At an operating temperature of 150C, the power consumptions of these three sensors are found to be 24 mW, 223 mW and 1240 mW, respectively. The resulting experimental data indicate that the proposed oxygen sensors are capable of detecting oxygen with concentrations ranging from 21% to 50%, and that they exhibit a linear output behavior. At an operating temperature of 180C, the proposed flow sensor demonstrates a linear behavior over a range of flow velocity from 0-10 m/sec.
Besides, this thesis develops an automated oxygen concentration control and measurement system which can simulate the miniscule respiratory variations of a premature infant and can subsequently establish a suitable oxygen concentration environment to ensure the infant’s well being. The proposed system can also automatically measure the properties of the oxygen sensors, including their resistance characteristics at different oxygen concentrations, the relationship between their sensitivity and the oxygen concentration, and the influence of working temperature and humidity upon their sensitivity. The measurement data is acquired locally and can then be transmitted to a remote PC via the Internet.

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