摘要:
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.
摘要:
A multimodal integrated circuit (IC) is provided, comprising, first (74) and second (76) semiconductor (SC) devices, and first (78) and second (80) integrated passive devices (IPDs) coupled, respectively, to the first (74) and second (76) SC devices, wherein the first IPD (78) overlies the second SC device (76) and the second IPD (80) overlies the first SC device (74) chosen such that the underlying SC device (74, 76) is not active at the same time as its overlying IPD (80, 78). By placing the IPDs (78, 80) over the SC devices (76, 74) a compact IC layout is obtained. Since the overlying IPD (78, 80) and underlying SC (76, 74) are not active at the same time, undesirable cross-talk (68, 69) between the IPDs (78, 80) and the SC devices (76, 74) is avoided. This arrangement applies to any IC having multiple signal paths (RF1, RF2) where the IPDs (78, 80) of a first path (RF1, RF2) may be placed over the SC devices (76, 74) of a second path (RF2, RF1) not active at the same time. This is especially useful with high frequencies ICs.
摘要:
A multimodal integrated circuit (IC) is provided, comprising, first (74) and second (76) semiconductor (SC) devices, and first (78) and second (80) integrated passive devices (IPDs) coupled, respectively, to the first (74) and second (76) SC devices, wherein the first IPD (78) overlies the second SC device (76) and the second IPD (80) overlies the first SC device (74) chosen such that the underlying SC device (74, 76) is not active at the same time as its overlying IPD (80, 78). By placing the IPDs (78, 80) over the SC devices (76, 74) a compact IC layout is obtained. Since the overlying IPD (78, 80) and underlying SC (76, 74) are not active at the same time, undesirable cross-talk (68, 69) between the IPDs (78, 80) and the SC devices (76, 74) is avoided. This arrangement applies to any IC having multiple signal paths (RF1, RF2) where the IPDs (78, 80) of a first path (RF1, RF2) may be placed over the SC devices (76, 74) of a second path (RF2, RF1) not active at the same time. This is especially useful with high frequencies ICs.
摘要:
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). When used in pairs (Q1-3, Q4-6) to form a variable switched attenuator, the first FET (Q1-3) is a pass device and the second FET (Q4-6) is a shunt device that respectively bridge two series resistors (R1, R2) and block a shunt resistor (R3) of a T-type attenuator.
摘要:
A power transistor (210) comprises a plurality of unit cell devices (212), a base contact configuration, an emitter contact configuration, and a collector contact configuration. The plurality of unit cell devices is arranged along an axis (194), each unit cell device including base (80), emitter (82), and collector (84) portions. The base contact configuration includes (i) a first base feed (150) coupled to the base portion of each unit cell device via a first end of at least one base finger (154) associated with a corresponding unit cell device and (ii) a second base feed (152) coupled to the base portion of each unit cell device via an opposite end of the at least one base finger associated with the corresponding unit cell device. The emitter contact configuration includes (i) a first emitter feed (172) coupled to the emitter portion of each unit cell device via a first end of an emitter metallization (176) associated with a corresponding unit cell device and (ii) a second emitter feed (174) coupled to the emitter portion of each unit cell device via an opposite end of the emitter metallization associated with the corresponding unit cell device. The collector contact configuration includes a collector feed (188) coupled to the collector portion of each unit cell device.
摘要:
An enhancement mode RF device and method of fabrication includes a stack of compound semiconductor layers, including a central layer defining a device channel, a doped cap layer, and a buffer epitaxially grown on a substrate. Source and drain implant areas, extending at least into the buffer, are formed to define an implant free area in the device channel between the source and drain. Source and drain metal contacts are positioned on an upper surface of the central layer. Several layers of insulation and dielectric are positioned over the device and a gate opening is formed and filled with gate metal. During epitaxial growth, the doped cap layer is tailored with a thickness and a doping to optimize channel performance including gate-drain breakdown voltage and channel resistance.
摘要:
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). Bias resistances (132, 134) are provided between the sources (72, 133) and control terminals (122, 124) so as to provide a DC path between the control terminals (122, 124) that maintains the source (72, 133) voltage at the proper bias potential for enhancement mode operation.
摘要翻译:提供了用于RF开关(100,200)的方法和装置。 在优选实施例中,该装置包括一个或多个多栅极n沟道增强型FET晶体管(50,112,114)。 当成对使用时,每个都具有耦合到第一公共RF I / O端口(116)的源极(74,133)和分别耦合到第二和第三RF I / O端口(118,120)的漏极, 和分别耦合到第一和第二控制端(122,124)的门(136,138)。 FET(50)的多栅极区域(66,68)平行耦合,间隔开并且串联地布置在源极(72)和漏极(76)之间。 轻度掺杂的n区(Ldd,Lds)被串行地布置在间隔开的多栅极区(66,68)之间,轻掺杂的n-区(Ldd,Lds)被更重掺杂的n区分离( 84)。 偏置电阻(132,134)设置在源极(72,133)和控制端子(122,124)之间,以便在维持源极(72,133)和控制端子(122,124)之间提供DC路径, 电压处于适当的偏置电位,用于增强模式操作。
摘要:
A power transistor (210) comprises a plurality of unit cell devices (212), a base contact configuration, an emitter contact configuration, and a collector contact configuration. The plurality of unit cell devices is arranged along an axis (194), each unit cell device including base (80), emitter (82), and collector (84) portions. The base contact configuration includes (i) a first base feed (150) coupled to the base portion of each unit cell device via a first end of at least one base finger (154) associated with a corresponding unit cell device and (ii) a second base feed (152) coupled to the base portion of each unit cell device via an opposite end of the at least one base finger associated with the corresponding unit cell device. The emitter contact configuration includes (i) a first emitter feed (172) coupled to the emitter portion of each unit cell device via a first end of an emitter metallization (176) associated with a corresponding unit cell device and (ii) a second emitter feed (174) coupled to the emitter portion of each unit cell device via an opposite end of the emitter metallization associated with the corresponding unit cell device. The collector contact configuration includes a collector feed (188) coupled to the collector portion of each unit cell device.