Semiconductor device contg. transistors connected in series - esp. two n-channel silicon gate transistors with low overlap capacitance

摘要

A p-type semiconductor substrate(30) is provided with two transistors(10,11). Transistor(10) has an n+ source zone(12); and a drain zone(13) which is also used as the source zone for transistor(11); the latter has a separate n+ drain zone(14). Two gate oxide layers(22,23) are provided with two separate poly Si gate electrodes(15,16). Electrodes(15,16) are sepd. by an oxide layer(21) which blends into oxide(23). Two channel zones(24,25) exist below layers(22,23), and are formed by inversion according to the voltage applied to electrodes(15,16). Substrate(30) is pref. Si; and the gate insulator layers(22,23) are pref. SiO2. The device has a small size and can be used in integrated MOS circuits operating at high speed in read-amplifiers.