Abstract: A low leakage current switch device (110) is provided which includes a GaN-on-Si substrate (11-43) covered by a passivation surface layer (43) in which a T-gate electrode with sidewall extensions (48) is formed and coated with a conformal passivation layer (49) so that the T-gate electrode sidewall extensions are spaced apart from the underlying passivation surface layer (43) by the conformal passivation layer (49).

Abstract: A low leakage current switch device (110) is provided which includes a GaN-on-Si substrate (11-43) covered by a passivation surface layer (43) in which a T-gate electrode with sidewall extensions (48) is formed and coated with a conformal passivation layer (49) so that the T-gate electrode sidewall extensions are spaced apart from the underlying passivation surface layer (43) by the conformal passivation layer (49).

Abstract: A low leakage current switch device (110) is provided which includes a GaN-on-Si substrate (11-13) covered by a passivation surface layer (43) in which a T-gate electrode with sidewall extensions (48) is formed and coated with a conformal passivation layer (49) so that the T-gate electrode sidewall extensions are spaced apart from the underlying passivation surface layer (43) by the conformal passivation layer (49).

Abstract: A low leakage current switch device (110) is provided which includes a GaN-on-Si substrate (11-13) covered by a passivation surface layer (43) in which a T-gate electrode with sidewall extensions (48) is formed and coated with a conformal passivation layer (49) so that the T-gate electrode sidewall extensions are spaced apart from the underlying passivation surface layer (43) by the conformal passivation layer (49).

Abstract: An integrated circuit includes a p-well block region having a high resistivity due to low doping concentration formed in a region of a substrate for providing noise isolation between a first circuit block and a second circuit block. The integrated circuit further includes a guard region formed surrounding the p-well block region for providing noise isolation between the first circuit block and the second circuit block.

Abstract: A method of fabricating an enhancement mode semiconductor device comprises providing a compound semiconductor substrate, epitaxially growing on the substrate a first portion of a buffer, the first portion including gallium arsenide (GaAs), growing a second portion of the buffer, the second portion including a high V/III ratio and high aluminum (Al) mole fraction aluminum gallium arsenide (AlGaAs), and epitaxially growing a stack of compound semiconductor layers on the buffer. An enhancement mode semiconductor device is then formed in the stack.

Abstract: Method and apparatus are provided for routing interconnects of a dual-gate electronic device operating in a differential configuration. An electronic apparatus formed on a substrate is provided comprising a first interconnect (40, 42, 44) configured to couple to a first region of the substrate, a first gate (22, 24, 26, 28) coupled to the first interconnect and configured to receive a first differential input, a second interconnect (30, 32, 34, 36, 38) parallel to the first interconnect and configured to couple to a second region of the substrate, and a second gate (20) coupled to the second interconnect and configured to receive a second differential input. The first gate is parallel to the first interconnect, and the second gate is parallel to the second interconnect.

Abstract: A system-on chip (SOC) (100) and method of isolating noise in a SOC, including a plurality of noise sensitive circuit blocks (120, 220) and ESD protected pads (302, 304, 306, 308, 310, 312, and 314). A VDD isolation pad (302) is connected to an N well ring (124) of the first noise sensitive circuit (120) to collect noise from the substrate (110) and isolate the circuit from the P well region (112). A ground protected pad (304) is connected to an isolated P well (126) of a first noise sensitive circuit (120). The ground pad (304) collects noise from the isolated P well (126) and sends it to ground. A dedicated ground isolation pad (306) is connected to a P well ring (224) of a second noise sensitive circuit (220). The dedicated ground isolation pad (306) collects noise from the P well ring (224) and sends it to ground.

Abstract: Methods are provided for forming a semiconductor device from a substrate comprising a bottom gate layer, a channel layer overlying the bottom gate layer, and a top gate structure formed over the channel layer. First, a hardmask comprising a first material interposed between a second material and a third material is deposited over a portion of the top gate structure. Then, the hardmask and top gate structure are encapsulated with an insulating material to form a spacer. A channel structure is formed from the channel layer, and the channel structure is disposed under the spacer. A bottom gate structure is formed from the bottom gate layer, and the bottom gate structure is disposed under the channel structure. Then, a source/drain contact is formed around the bottom gate structure.

Abstract: In one embodiment, a semiconductor device (500) includes a buffer layer (504) formed over a substrate (502). An AlxGa1-xAs layer (506) is formed over the buffer layer (504) and has a first doped region (508) formed therein. An InxGa1-xAs channel layer (512) is formed over the AlxGa1-xAs layer (506). An AlxGa1-xAs layer (518) is formed over the InxGa1-xAs channel layer (512), and the AlxGa1-xAs layer (518) has a second doped region formed therein. A GaAs layer (520) having a first recess is formed over the AlxGa1-xAs layer (518). A control electrode (526) is formed over the AlxGa1-xAs layer (518). A doped GaAs layer (524) is formed over the undoped GaAs layer (520) and on opposite sides of the control electrode (526) and provides first and second current electrodes. When used to amplify a digital modulation signal, the semiconductor device (500) maintains linear operation over a wide temperature range.

Abstract: Methods and apparatus are provided for RF switches (100, 200). In a preferred embodiment, the apparatus comprises one or more multi-gate n-channel enhancement mode FET transistors (50, 112, 114). When used in pairs (112, 114) each has its source (74, 133) coupled to a first common RF I/O port (116) and drains coupled respectively to second and third RF I/O ports (118, 120), and gates (136, 138), coupled respectively to first and second control terminals (122, 124). The multi-gate regions (66, 68) of the FETs (50) are parallel coupled, spaced-apart and serially arranged between source (72) and drain (76). Lightly doped n-regions (Ldd, Lds) are provided serially arranged between the spaced-apart multi-gate regions (66, 68), the lightly doped n-regions (Ldd, Lds) being separated by more heavily doped n-regions (84).

Abstract: Methods and apparatus are provided for RF switches (504, 612) integrated in a monolithic RF transceiver IC (500) and switched gain amplifier (600). Multi-gate n-channel enhancement mode FETs (50, 112, 114, Q1-3, Q4-6) are used with single gate FETs (150), resistors (Rb, Rg, Re, R1-R17) and capacitors (C1-C3) formed by the same manufacturing process. The multiple gates (68) of the FETs (50, 112, 114, Q1-3, Q4-6) are parallel coupled, spaced-apart and serially arranged between source (72) and drain (76). When used in pairs (112, 114) to form a switch (504) for a transceiver (500) each FET has its source (74) coupled to an antenna RF I/O port (116, 501) and drains coupled respectively to second and third RF I/O ports (118, 120; 507, 521) leading to the receiver side (530) or transmitter side (532) of the transceiver (500). The gates (136, 138) are coupled to control ports (122, 124; 503, 505; 606, 608).

Abstract: A semiconductor structure includes a first semiconductor layer, a second semiconductor layer over the first semiconductor layer, a third semiconductor layer over the second semiconductor layer, and a fourth semiconductor layer over the third semiconductor layer. A first conductive portion is coupled to the first semiconductor layer, and a second conductive portion is formed over the first semiconductor layer.

Abstract: A method of fabricating apparatus, and the apparatus, for providing low voltage temperature compensation in a single power supply HFET including a stack of epitaxially grown compound semiconductor layers with an HFET formed in the stack. A Schottky diode is formed in the stack adjacent the HFET during the formation of the HFET. The HFET and the Schottky diode are formed simultaneously, with a portion of one of the layers of metal forming the gate of the HFET being positioned in contact with a layer of the stack having a low bandgap (e.g. less than 0.8 eV) to provide a turn-on voltage for the Schottky diode of less than 1.8 Volts. The Schottky diode is connected to the gate contact of the HFET by a gate circuit to compensate for changes in current loading in the gate circuit with changes in temperature.

Abstract: A method of fabricating apparatus, and the apparatus, for providing low voltage temperature compensation in a single power supply HFET including a stack of epitaxially grown compound semiconductor layers with an HFET formed in the stack. A Schottky diode is formed in the stack adjacent the HFET during the formation of the HFET. The HFET and the Schottky diode are formed simultaneously, with a portion of one of the layers of metal forming the gate of the HFET being positioned in contact with a layer of the stack having a low bandgap (e.g. less than 0.8 eV) to provide a turn-on voltage for the Schottky diode of less than 1.8 Volts. The Schottky diode is connected to the gate contact of the HFET by a gate circuit to compensate for changes in current loading in the gate circuit with changes in temperature.