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The electrostatic discharge (ESD) characteristics of a three-body problem comprised of a charged human body approaching an electronic system with an interposed guard electrode are investigated. Capacitance coefficients were measured for various three conductor arrangements; for an assumed charge on the human body, body potentials were calculated and the relative effectiveness of different guard electrode geometries to control the ESD event compared. The results provide a better understanding of the fundamental principles involved in the ESD event involving three bodies and have application in the design of interfaces between the charged human body and electronic systems. Index Terms--Control, electrostatic discharge (ESD), human body.

Various models are used to simulate the electrostatic discharge (ESD) event associated with semiconductor devices; these include the human body model (HBM), the charged device model (CDM), and the field induced charged device model (FCDM). Maxwell's method is used to analyze these models to determine device potentials and the transfer of charge during typical discharges; existing test methods are also examined. A charge injection test method is introduced which provides control of the charge transferred to the device under test; it is proposed as a means to study charge related phenomena due to ESD.

The electrostatic wafer chuck is the most preferable handling method in advanced semiconductor manufactures. Even in a vacuum environment, it enables not only the ability to retain a wafer flat, but also to enhance heat transfer through the whole surface area because of firm contact. We have investigated the fundamental characteristics of an electrostatic chuck consisting of a pair of comb-type electrodes and a thin polymer film as a dielectric layer. In order to prevent breakdown between electrodes, the air gap between electrodes was filled with sealing material. The electrostatic force acting on the 4-in silicon wafer is measured. Several types of insulating sealants and dielectric films were examined. The attractive force increased with the square of the applied voltage in the region of lower applied voltage and gradually saturated at higher voltage. The maximum force obtained in our experiments was approximately 30 N. These experimental results proved the high potentiality in actual use of the electrostatic chuck for silicon wafer handling. However, a few problems have to be overcome. Although the higher electrostatic force can be gained with the thinner dielectric layer, the thin polymer film is easily deformed and torn by tension when the object starts moving. Index Terms--Dielectric layer, electrostatic force, silicon wafer, wafer handling.