الفهرس 
Chapter 1: Introduction to MEMSOnly 14 pages are availabe for public view
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Abstract
Microelectromechanical Systems (MEMS) are now one of the most growing engineering fields. This field is mainly based on the use of the standard integrated circuits technology and some additional developed processes to create a new enabling technology that can be used in diverse applications. The main elements of MEMS are sensors, actuators and microelectronics, where the electrostatic property is the principle of operation of most MEMS actuators. Electrostatic parallel-plate actuators are prevalent in Micro-Electro-Mechanical Systems (MEMS) because they are compatible with micro fabrication technology and consume low power. The parallel-plate electrostatic actuator is a fundamental part in many microelectromechanical systems (MEMS) when tuning, positioning, or controlled movement is needed. The objective of this research is to introduce the parallel plate electrostatic actuator with a detailed study of its operation and characteristics. Studies have proven that the parallel plate electrostatic actuator can be used as a gas sensor for different gases by applying DC voltage to the two parallel plates of the actuator. MEMS-based gas sensor which is based on the parallel plate electrostatic actuator can easily detect toxic gases in laboratories, factories and petroleum industry. Environmentalists use such sensors to detect gas leaks and monitor industrial emissions. The proposed sensor consists of a sensing material and an electronic circuit that detects the change in gas concentration. Compared to the commercial sensors that quantify the concentration of the gas in analog mode, the binary gas sensor does not measure the concentration. It states the concentration of the gas using only two states “0” for the concentration below threshold (safe operation) and “1” for the concentration above threshold (unsafe operation).