摘要:
Integrated circuit structure and processing is provided for a high power limiter including at least a first anti-parallel array of monolithically integrated Schottky diodes. In a further embodiment, integrated circuit structure and processing is provided for an MMIC, microwave and millimeter wave monolithic integrated circuit, including an amplifier and a high power limiter monolithically integrated on the same substrate.
摘要:
The fabrication of high performance and reliable Buried Channel Field Effect Transistor (BCFET) using Schottky gate junction and heavily doped N layers for the source and drain electrode is described. The BCFET is composed of a semi-insulating substrate in which two N layers for the drain electrodes and one N layer for the source electrode are formed in one of the semi-insulating surface. The N source electrode is centrally located between the two N electrodes and all three lie in the same plane. The source and drain electrodes are separated by a thin semi-insulating layer, the length of which can range from 0.5 micron to several micron range, depending on the desired voltage breakdown. A Schottky gate is defined in an active N layer directly above the source N layer. The ohmic contacts for the source and drain N layers are defined several microns away from the Schottky junction, resulting in a considerable improvement in device reliability. Reliability is further enhanced by the fact that the resulting device is buried within the material where it is insulated from the ambient.
摘要:
An MOMS tunnel emission transistor is provided by a plurality of mesa stacked horizontal layers including at least one semiconductor layer (63) having an exposed edge (68) at a generally vertical side (67) of the mesa, such as the 111 plane. A first metal layer (66) has a generally vertical portion (72) extending along the side of the mesa and forming a schottky junction with the edge of the semiconductor layer. A generally vertical oxide layer (70) is on the first metal layer, and a second metal layer (71) is on the oxide. The MOMS tunnel emission transistor is formed by metal (71) - oxide (70) - metal (66) - semiconductor (63).
摘要:
A mesa semiconductor device, including a metal film conductor located on the upper surface of the device about the base of the mesa to reduce skin effect loss.
摘要:
A semiconductor device and processing technique is provided for monolithic integration of a single crystal compound element semiconductor on a ceramic substrate. A high resistivity semi-insulating buffer layer is epitaxially grown on the ceramic substrate and has an elastically transitional lattice constant matching at its lower surface the lattice constant of the ceramic substrate, and matching at its upper surface the lattice constant of the semiconductor layer.
摘要:
Method for fabrication of quasi-monolithic microwave integrated circuits in which metals, oxides, and processes are selected to enable fabrication of the circuits by first producing many layers of metals and oxides in situ without removing the circuit from its environmental chamber. This reduces inclusion of contaminating chemical films and particles between the desired layers. Circuit elements are then defined by processing of the layers by photolithography and other processes from the top of the circuit downward. Lumped and distributed capacitors, resistors, inductors, transmission lines, and contacts for active devices are monolithically defined, with a reduced number of process steps.
摘要:
During fabrication of monolithic microwave integrated circuits, active devices having sources, gates, drains, and/or Schottky barrier junctions are first provided for an epitaxial layers. Then many layers of metals and oxides are produced thereover in situ without removing the circuit from its environmental chamber. Circuit elements are then defined by processing of the many layers sequentially by photolithography and other processes from the top of the chip downward. Certain combinations of metals, oxides, and processes are selected to enable fabrication of circuits from the top down in this way. This reduces inclusion of contaminating chemical films and particles between the desired layers. Lumped and distributed capacitors, resistors, inductors, transmission lines, contacts, and complete active devices are monolithically defined, with a reduced number of process steps. An all-refractory MESFET is described, having a Schottky barrier gate and nonalloyed ohmic contacts for source and drain producible at room temperatures. Source, gate, and drain can be defined with a single mask. A thinner gold layer is formed for FET contacts than for other circuit conductors and elements by means of a configured tantalum layer buried in a thick gold layer.
摘要:
The fabrication of high performance and reliable Buried Channel Field Effect Transistor (BCFET) using Schottky gate junction and heavily doped N layers for the source and drain electrode is described. The BCFET is composed of a semi-insulating substrate in which two N layers for the drain electrodes and one N layer for the source electrode are formed in one of the semi-insulating surface. The N source electrode is centrally located between the two N drain electrodes and all three lie in the same plane. The source and drain electrodes are separated by a thin semi-insulating layer, the length of which can range from 0.5 micron to several micron range, depending on the desired voltage breakdown. A Schottky gate is defined in an active N layer directly above the source N layer. The ohmic contacts for the source and drain N layers are defined several microns away from the Schottky junction, resulting in a considerable improvement in device reliability. Reliability is further enhanced by the fact that the resulting device is buried within the material where it is insulated from the ambient.
摘要:
A tunnel diode having a generally rectangular junction area in the 10.sup.-10 to 10.sup.-11 cm.sup.2 range formed in a quasi-planar structure of a first metal, an oxide of the first metal and a second metal. The first metal may be tantalum or other similarly slow oxidizable metals. The second metal may be selected from a group also including tantalum. For a symmetrical junction, the first and second metals are the same, however, for an asymmetrical junction the first and second metals are different. To reduce the diode series electrical and thermal resistance, a gold layer is deposited over the first and second metals. The gold layer over the first metal is deposited everywhere except at or within a few microns of the junction. The device provides a small junction area and also negligible parasitic shunt capacitance which are necessary for efficient room temperature operation at frequencies in the submillimeter to optical region. Direct and heterodyne detection in the 10 microns region has been successfully achieved with these devices.
摘要:
A method for forming ohmic contacts of gold and germanium gold on a gallium arsenide substrate in which a layer of silicon dioxide is placed over the gold in the contact area prior to sinter alloying to improve wetting and reduce contact resistance.