InGaAs／GaAs异质结构材料及器件应用

概述了ＩｎＧａＡｓ／ＧａＡｓ异质结构材料用于制作微波器件的优越性，叙述了材料的ＭＢＥ生长、输运特性和掺杂分布，以及用于制作Ｋｕ波段低噪声高增益ＨＦＥＴ的结果：栅长０．５μｍ，１２ＧＨｚ下噪声系数０．９３ｄＢ，相关增益９ｄＢ。     

Ultralow-noise W-band pseudomorphic InGaAs HEMT's

Low-noise planar doped pseudomorphic (PM) InGaAs high-electron-mobility transistors (HEMTs) with a gate length of 0.1 μm for W-band operation are discussed. These devices feature a multiple-finger layout with air bridges interconnecting the sources to reduce gate resistance. The device exhibits a minimum noise figure of 2.5 dB with an associated gain of 4.7 dB at 92.5 GHz. This result demonstrates the feasibility of using PM InGaAs HEMTs for W-band low-noise receivers without the need for using lattice-matched InP HEMTs     

60-GHz pseudomorphicAl0.25Ga0.75As/In0.28Ga0.72As low-noise HEMTs

V-band low-noise planar-doped pseudomorphic (PM) InGaAs high electron mobility transistors (HEMTs) were fabricated with an indium mole fraction of 28% in the InGaAs channel. A device with 0.15-μm T-gate achieved a minimum noise figure of 1.5 dB with an associated gain of 6.1 dB at 61.5 GHz     

Very high gain millimeter-wave InAlAs/InGaAs/GaAs metamorphicHEMT's

We report the first demonstration of W-band metamorphic HEMTs/LNA MMICs using an AlGaAsSb lattice strain relief buffer layer on a GaAs substrate. 0.1×50 μm low-noise devices have shown typical extrinsic transconductance of 850 mS/mm with high maximum drain current of 700 mA/mm and gate-drain breakdown voltage of 4.5 V. Small-signal S-parameter measurements performed on the 0.1-μm devices exhibited an excellent f_T of 225 GHz and maximum stable gain (MSG) of 12.9 dB at 60 GHz and 10.4 dB at 110 GHz. The three-stage W-band LNA MMIC exhibits 4.2 dB noise figure with 18 dB gain at 82 GHz and 4.8 dB noise figure with 14 dB gain at 89 GHz, The gain and noise performance of the metamorphic HEMT technology is very close to that of the InP-based HEMT     

An ultra-low power InAs/AlSb HEMT Ka-band low-noise amplifier

The first antimonide-based compound semiconductor (ABCS) MMIC, a Ka-Band low-noise amplifier using 0.25-/spl mu/m gate length InAs/AlSb metamorphic HEMTs, has been fabricated and characterized on a 75 /spl mu/m GaAs substrate. The compact 1.1 mm/sup 2/ three-stage Ka-band LNA demonstrated an average of 2.1 dB noise-figure between 34-36 GHz with an associated gain of 22 dB. The measured dc power dissipation of the ABCS LNA was an ultra-low 1.5 mW per stage, or 4.5 mW total. This is less than one-tenth the dc power dissipation of a typical equivalent InGaAs/AlGaAs/GaAs HEMT LNA. Operation with degraded gain and noise figure at 1.1 mW total dc power dissipation is also verified. These results demonstrate the outstanding potential of ABCS HEMT technology for mobile and space-based millimeter-wave applications.     

94-GHz 0.1-μm T-gate low-noise pseudomorphic InGaAs HEMTs

Fabrication of state-of-the-art W-band 0.1-μm T-gate pseudomorphic (PM) InGaAs high electron mobility transistors (HEMTs) is reported. This device achieved a noise figure of 2.1 dB with an associated gain of 6.3 dB at 93.5 GHz. The device has a maximum gain of 9.6 dB at 94 GHz, which extrapolates to an F_max of 290 GHz. This noise figure is claimed to be the lowest ever reported for HEMTs fabricated on GaAs substrates at this frequency range     

Super low-noise HEMTs with a T-shaped WSix gate

A T-shaped quarter-micron gate structure composed of WSi_x /Ti/Pt/Au has been developed for low-noise AlGaAs/GaAs HEMTs. The gate resistance R_g was reduced to 0.3 Ω for devices with 200 μm-wide gates despite using WSi_x, and the source resistance R_s reached 0.28 Ω mm by minimising the source-gate distance using a self-alignment technique. This HEMT exhibited the lowest reported noise figure of 0.54 dB with an associated gain of 12.1 dB at 12 GHz     

110-120-GHz monolithic low-noise amplifiers

The authors discuss the development of 110-120-GHz monolithic low-noise amplifiers (LNAs) using 0.1-mm pseudomorphic AlGaAs/InGaAs/GaAs low-noise HEMT technology. Two 2-stage LNAs have been designed, fabricated, and tested. The first amplifier demonstrates a gain of 12 dB at 112 to 115 GHz with a noise figure of 6.3 dB when biased for high gain, and a noise figure of 5.5 dB is achieved with an associated gain of 10 dB at 113 GHz when biased for low-noise figure. The other amplifier has a measured small-signal gain of 19.6 dB at 110 GHz with a noise figure of 3.9 dB. A noise figure of 3.4 dB with 15.6-dB associated gain was obtained at 113 GHz. The authors state that the small-signal gain and noise figure performance for the second LNA are the best results ever achieved for a two-stage HEMT amplifier at this frequency band     

Extremely low noise InGaAs/InAlAs HEMT grown by MOCVD

MOCVD-grown InGaAs/InAlAs HEMTs with excellent noise performance comparable to that of MBE-grown devices have been successfully fabricated. A minimum noise figure lower than 0.30 dB has been obtained with an associated gain of approximately 15 dB at 12 GHz. Furthermore, devices in ceramic packages have exhibited a minimum noise figure of 0.42 dB.<>     

W-band low-noise InAlAs/InGaAs lattice-matched HEMTs

Very low-noise 0.15-μm gate-length W-band In_0.52 Al_0.48As/In_0.53Ga_0.47As/In _0.52Al_0.48As/InP lattice-matched HEMTs are discussed. A maximum extrinsic transconductance of 1300 mS/mm has been measured for the device. At 18 GHz, a noise figure of 0.3 dB with an associated gain of 17.2 dB was measured. The device also exhibited a minimum noise figure of 1.4 dB with 6.6-dB associated gain at 93 GHz. A maximum available gain of 12.6 dB at 95 GHz, corresponding to a maximum frequency of oscillation, f_max, of 405 GHz (-6-dB/octave extrapolation) in the device was measured. These are the best device results yet reported. These results clearly demonstrate the potential of the InP-based HEMTs for low-noise applications, at least up to 100 GHz     

Millimeter-wave low-noise and high-power metamorphic HEMTamplifiers and devices on GaAs substrates

This paper reports on state of-the-art HEMT devices and circuit results utilizing 32% and 60% indium content InGaAs channel metamorphic technology on GaAs substrates. The 60% In metamorphic HEMT (MHEMT) has achieved an excellent 0.61-dB minimum noise figure with 11.8 dB of associated gain at 26 GHz. Using this MHEMT technology, two and three-stage Ka-band low-noise amplifiers (LNAs) have demonstrated <1.4-dB noise figure with 16 dB of gain and <1.7 with 26 dB of gain, respectively. The 32% In MHEMT device has overcome the <3.5-V drain bias limitation of other MHEMT power devices, showing a power density of 650 mW/mm at 35 GHz, with V_ds=6 V     

Monolithic integration of pseudomorphic power and low-noise HEMTs

Monolithic integration of pseudomorphic power and low-noise high electron mobility transistors (HEMTs) on a GaAs substrate has been demonstrated using specially designed multiple epitaxial layers. MBE-grown layers with three heterojunctions were selectively recessed to provide optimum structures for low-noise and power operations. At 18 GHz, a record power-added efficiency of 59% with 8 dB gain and 0.4 W/mm power density was obtained for the power HEMT. The low-noise device from the same slice achieved a noise figure of 1 dB with 9 dB associated gain at the same frequency.<>     

Super-low-noise performance of direct-ion-implanted 0.25-μm-gateGaAs MESFET's

The authors report on advanced ion implantation GaAs MESFET technology using a 0.25-μm `T' gate for super-low-noise microwave and millimeter-wave IC applications. The 0.25×200-μm-gate GaAs MESFETs achieved 0.56-dB noise figure with 13.1-dB associated gain at 50% I_DSS and 0.6 dB noise figure with 16.5-dB associated gain at 100% I_DSS at a measured frequency of 10 GHz. The measured noise figure is comparable to the best noise performance of AlGaAs/GaAs HEMTs and AlGaAs/InGaAs/GaAs pseudomorphic HEMTs     

Very low-noise Al/sub 0.3/Ga/sub 0.7/As/Ga/sub 0.65/In/sub 0.35/As/GaAs single quantum-well pseudomorphic HEMTs

AlGaAs/GaInAs/GaAs pseudomorphic HEMTs with an InAs mole fraction as high as 35% in the channel has been successfully fabricated. The device exhibits a maximum extrinsic transconductance of 700 mS/mm. At 18 GHz, a minimum noise figure of 0.55 dB with 15.0 dB associated gain was measured. At 60 GHz, a minimum noise figure as low as 1.6 dB with 7.6 dB associated gain was also obtained. This is the best noise performance yet reported for GaAs-based HEMTs.<>     

A W-band InAs/AlSb low-noise/low-power amplifier

The first W-band antimonide based compound semiconductor low-noise amplifier has been demonstrated. The compact 1.4-mm/sup 2/ three-stage co-planar waveguide amplifier with 0.1-/spl mu/m InAs/AlSb high electron mobility transistor devices is fabricated on a 100-/spl mu/m GaAs substrate. Minimum noise-figure of 5.4dB with an associated gain of 11.1 dB is demonstrated at a total chip dissipation of 1.8 mW at 94 GHz. Biased for higher gain, 16/spl plusmn/1 dB is measured over a 77-103 GHz frequency band.     

Microwave noise characteristics of AlGaN/GaN HEMTs on SiC substrates for broad-band low-noise amplifiers

This letter reports high-performance passivated AlGaN/GaN high electron-mobility transistors (HEMTs) with 0.25-/spl mu/m gate-length for low noise applications. The devices exhibited a minimum noise figure (NF/sub min/) of 0.98 dB and an associated gain (G/sub a/) of 8.97 dB at 18 GHz. The noise resistance (R/sub n/), the measure of noise sensitivity to source mismatch, is 31/spl Omega/ at 18 GHz, which is relatively low and suitable for broad-band low noise amplifiers. The noise modeling analysis shows that the minimum noise figure of the GaN HEMT can be reduced further by reducing noise contributions from parasitics. These results demonstrate the viability of AlGaN/GaN HEMTs for low-noise as well as high power amplifiers.     

Extremely high gain 0.15 mu m gate-length InAlAs/InGaAs/InP HEMTs

High electron mobility transistors (HEMTs) based on the InAlAs/InGaAs heterojunction grown lattice matched to InP were fabricated with 0.15 mu m T-shaped gates. The use of an undoped InGaAs cap layer in the epitaxial structure leads to excellent gate characteristics and very high transistor gain. At 95 GHz, a maximum available gain of 13.6 dB was measured. A maximum frequency of oscillation f/sub max/ of 455 GHz was obtained by extrapolating from 95 GHz at -6 dB/octave. This is the best reported gain performance for any transistor.<>     

Noise performance at cryogenic temperatures at AlGaAs/InGaAs HEMT'swith 0.15-μm T-shaped WSix gates

T-shaped 0.15-μm WSi_x gate HEMTs have been fabricated on AlGaAs/InGaAs MBE wafers. Their S-parameters, output noise spectral density P_no, and noise temperatures T _e at cryogenic temperatures, were measured. The current gain cutoff frequency f_T increases from 61 GHz at 295 K to 87 GHz at 90 K. P_no and T_e measurements indicate that the hot-electron effect is noticeable at low temperatures at high drain current. At 30 GHz, the noise temperature is 19±3 K with an associated gain of 10.4 dB at the physical temperature of 20 K. The results demonstrate the great potential of AlGaAs/InGaAs HEMTs for low-temperature applications     

60 GHz low-noise high-electron-mobility transistors

The noise performance of 0.25 ?m-gate-length high-electron-mobility transistors at frequencies up to 62 GHz is reported. A room-temperature extrinsic transconductance gm of 480 mS/mm and a maximum frequency of oscillation fmax of 135 GHz are obtained for these transistors. At 30 and 40 GHz the devices exhibit minimum noise figures of 1.5 and 1.8 dB with associated gains of 10.0 and 7.5 dB, respectively. A minimum noise figure as low as 2.7 dB with an associated gain of 3.8 dB has also been measured at 62 GHz. This is the best noise performance ever reported for HEMTs at millimetre-wave frequencies. The results clearly demonstrate the potential of short-gate-length high-electron-mobility transistors for very low-noise applications for frequencies at least up to V-band.     

Half-micrometer gate-length ion-implanted GaAs MESFET with 0.8-dBnoise figure at 16 GHz

Ion-implanted GaAs MESFETs with half-micrometer gate length have been fabricated on 3-in-diameter GaAs substrates. At 16 GHz, a minimum noise figure of 0.8 dB with an associated gain of 6.3 dB has been measured. This noise figure is believed to be the lowest ever reported for 0.5- and 0.25-μm ion-implanted MESFETs, and is comparable to that for 0.25-μm HEMTs at this frequency. By using the Fukui equation and the fitted equivalent circuit model, a K_f factor of 1.4 has been obtained. These results clearly demonstrate the potential of ion-implanted MESFET technology for K-band low-noise integrated circuit applications