ANALOGUE SWITCH CAPACITOR CIRCUIT AND MANUFACTURE THEREOF

摘要

PURPOSE: To integrate a polycrystalline silicon thin film capacitor means, a thin film transistor switching means, a thin film amplifier means and an interconnecting means with pixel element on a common substrate. CONSTITUTION: N-channel TFT 110, p-channel TFT 120 and a capacitor 130 are formed on the same insulating crystal or a glass substrate 100. Each TFT has active polycrystalline silicon islands 112 and 122, gate oxide layers 114 and 124 and polycrystalline silicon gates 116 and 126. The capacitor 130 needs only one time additional ion implanting to make a conductive bottom plate 132 from an activator island and uses a TFT gate dielectric 134. The capacitor 130 is similar to polycrystalline silicon to a diffusion capacitor in an ordinary MOS analog process. Thereby, a parasitic capacitance that is related to any of plates can be ignored.