Abstract:
Voltage losses, and consequent reduced transconductance, can be overcome in metal-oxide-semiconductor (MOS) circuits by the use of a voltage variable coupling capacitor comprising a drain and a gate electrode. Since the capacitor is voltage variable, selective coupling is obtainable. In a dynamic memory cell, a voltage variable capacitor connected to the storage node selectively couples enabling to the storage node to increase the transconductance of the read transistor. Selective coupling is also used in apparatus ancillary to the memory cell to enhance the ''''refresh'''' operation. A flip-flop type of memory is also disclosed in which an enhanced output signal is obtained by selective coupling.
Abstract:
HIGH STABLITY, SELF-REGISTERED FIELD EFFECT TRANSISTORS ARE FORMED BY ETCHING THE METAL GATE ELECTRODE SIMULTANEOUSLY WITH EXPOSURE OF SURFACE ADJACENT AREAS OF A SEMICONDUCTIVE WAFER, GROWING AN ACTIVATOR CONTAINING GLASS ATOP ONLY THE EXPOSED AREAS OF THE WAFER BY PASSING A GASEOUS STREAM CONTAINING A MILD OXIDIZING AGENT AND AN ACTIVATOR IMPURITY ACROSS THE ETCHED FACE OF THE WAFER HEATED TO A TEMPERATURE BETWEEN 700*C. AND 1000*C., AND SUBSEQUENTLY BAKING THE SEMICONDUCTIVE WAFER IN A REDUCING ATMOSPHERE AT TEMPERATURES IN EXCESS OF 1000*C. TO FORM THE SOURCE AND DRAIN REGIONS OF THE SEMICONDUCTIVE WAFER. IN A PARTICULARLY PREFERRED EMBODIMENT, A GASEOUS STREAM CONTAINING 5-10% HYDROGEN AND 90-95% HELIUM OR ARGON IS BUBBLED THROUGH WATER AND ETHYL BORATE SOLUTIONS AT ROOM TEMPERATURE WHEREUPON THE STREAM IS PASSED OVER AN ETCHED WAFER TO FORM A SILICO-BORATE GLASS ATOP THE EXPOSED SILICON SURFACE. THE SEMICONDUCTIV WAFER THEN IS BAKED FOR APPROXIMATELY 4 HOURS AT 1000*C. IN A NITROGEN ATMOSPHERE CONTAINING 5-10% BY VOLUME HYDROGEN TO DRIVE THE ACTIVATOR IMPURITIES INTO THE WAFER. A TECHNIQUE FOR FORMING COMPLEMENTARY PAIRS OF HIGH STABILITY SELF-REGISTERED FIELD EFFECT TRANSISTORS ON A SINGLE SUBSTRATE ALSO IS DISCLOSED.
Abstract:
An improved method of bonding metal to a ceramic is described in which the metal is shaped, surface treated, and curved prior to heating the metal to form a eutectic bond between the metal and the ceramic. The surface treatment comprises heating the metal in a reactive atmosphere, e.g., in an oxidizing atmosphere to produce an oxide layer. The surface treatment is carried out at a temperature lower than the metal-metal oxide eutectic temperature.