Abstract: Desirably, a Schottky barrier semiconductor diode has low forward direction rising voltage and high inverse direction yield voltage. A semiconductor device is provided with a first metal producing a low Schottky barrier and a second metal producing a high Schottky barrier. The forward direction rising voltage is reduced on account of the first metal. The inverse direction yield voltage, which is decreased due to the lowered forward rising voltage, is compensated for upon linking of depletion regions generated by forming the PN junction under the first metal layer and not under the second metal layer. As a result, a high inverse yield voltage is realized.
Abstract: A semiconductor device, comprising a transistor, a constant voltage diode having a first end of a first conductivity type connected to an emitter of the transistor and a second end of a second conductivity type, a reverse current preventive diode having a first end of the first conductivity type connected to a collector of the transistor and a second end of the second conductivity type connected to the second end of the constant voltage diode, and a high speed diode reverse-bias connected between the transistor collector and the emitter of the transistor.
Abstract: A thin-film ROM device includes an array of open circuit and closed-circuit cells (5 to 8) formed from a stack of thin films (12,21,22,23,11) on a glass or other substrate (10). The semiconductor films (21,22,23) may be of hydrogenated amorphous silicon. At least one of the semiconductor films (21,22,23) is removed from some of the closed-circuit cell areas (5,7,8) before depositing the next film. In this way, at least a second type of thin-film diode (MIM, MIN, MIP) is formed having a different conduction characteristic to that of a first type (NIP), so increasing the information content of the ROM array. A lower semiconductor film (23) can be readily etched away from the lower electrode film (11) by a selective etching treatment in which the electrode film (11) acts as an etch stop. By monitoring emissions during plasma etching, an upper semiconductor film (21 or 22) can be removed from a lower semiconductor film (22 or 23).
Abstract: A Schottky barrier rectifier includes regions of different Schottky barrier heights. Preferably, alternating regions of relatively high and relative low barrier heights are provided on a semiconductor substrate and are electrically connected in parallel to form a single Schottky barrier rectifier. The alternating regions may be provided by laterally spaced apart regions of a first metal on the semiconductor substrate and a layer of a second metal on the regions of the first metal and on the semiconductor substrate between the regions of first metal. Alternatively, a plurality of spaced apart barrier altering regions, such as a plurality of shallow implants, are formed in the semiconductor substrate, and a continuous metal layer is formed on the semiconductor substrate. In yet another embodiment, plurality of laterally spaced apart trenches are formed in the semiconductor substrate.
Type:
Grant
Filed:
August 13, 1992
Date of Patent:
November 16, 1993
Assignee:
North Carolina State University at Raleigh
Abstract: Improvement of a high frequency device having metal layers, active semiconductor layers and other semiconductor layers which make use of carrier avalanche or carrier injection induced by a reverse bias voltage for amplification or oscillation of high frequency waves. The active semiconductor layers are made of semiconductor diamond. High heat conductivity and high insulation breakdown voltage of diamond heighten the output power of oscillation or amplification.