0.2-/spl mu/m gate-length InGaP-InGaAs DCFETs for C-band MMIC amplifier applications

A C-band In/sub 0.49/Ga/sub 0.51/P-In/sub 0.15/Ga/sub 0.85/As doped-channel FET (DCFET) monolithic power amplifier was designed and fabricated using low-k benzocyclobutene (BCB) interlayer technology. With a photosensitive low-k BCB interlayer (/spl epsiv/=2.7), not only can the circuit's passivation layer, but also the capacitor insulator, via holes, and bridge process be realized simultaneously, where the process complexity and cost can be reduced. In addition, a 0.2-/spl mu/m T-shaped gate InGaP-InGaAs doped-channel FET with a high current density and a high linearity is introduced to the amplifier using the e-beam lithography. This C-band power amplifier can achieve a linear power gain of 9.3 dB and an output power of 15.3 dBm, which proves that this novel MMIC process using low-k BCB interlayer technology is attractive for microwave and millimeter wave circuit applications.     

A coplanar X-band AlGaN/GaN power amplifier MMIC on s.i. SiC substrate

This work presents a two-stage high-power amplifier monolithic microwave integrated circuit (MMIC) operating between 9 GHz and 11 GHz based on a fully integrated AlGaN/GaN high electron mobility transistor (HEMT) technology on s.i. SiC substrate and is suitable for radar applications. The MMIC device with a chip size of 4.5/spl times/3 mm/sup 2/ yields a linear gain of 20 dB and a maximum pulsed saturated output power of 13.4 W at 10 GHz equivalent to 3.3 W/mm at V/sub DS/=35V, 10% duty cycle, and a gain compression level of 5 dB. Further, dc reliability data are given for the MMIC HEMT technology.     

A 4-W X-band compact coplanar high-power amplifier MMIC with 18-dB gain and 25% PAE

The performance of a compact coplanar microwave monolithic integrated circuit (MMIC) amplifier with high output power in the X-band is presented. Based on our 0.3-/spl mu/m gate-length GaAs power pseudomorphic high electron mobility transistor (PHEMT) process on 4-in wafer, this two-stage amplifier, having a chip size of 16 mm/sup 2/, averages 4-W continuous-wave (CW) and 25% mean power-added efficiency (PAE) in the X-band, with more than 18-dB linear gain. Peak output powers of P/sub -1dB/=36.3dBm (4.3 W) and P/sub sat/ of 36.9 dBm (4.9 W) at 10 GHz with a PAE of 50% were also measured. Compared to previously reported X-band coplanar high-power amplifiers, this represents a chip size reduction of 20%, comparable to the size of compact state-of-the-art microstrip power amplifiers.     

High-power monolithic AlGaN/GaN HEMT oscillator

A monolithic X-band oscillator based on an AlGaN/GaN high electron mobility transistor (HEMT) has been designed, fabricated, and characterized. A common-gate HEMT with 1.5 mm of gate width in conjunction with inductive feedback is used to generate negative resistance. A high Q resonator is implemented with a short-circuit low-loss coplanar waveguide transmission line. The oscillator delivers 1.7 W at 9.556 GHz into 50-/spl Omega/ load when biased at V/sub ds/=30 V and V/sub gs/=-5 V, with dc-to-RF efficiency of 16%. Phase noise was estimated to be -87 dBc/Hz at 100-kHz offset. Low-frequency noise, pushing and pulling figures, and time-domain characterization have been performed. Experimental results show great promise for AlGaN/GaN HEMT MMIC technology to be used in future high-power microwave source applications.     

Miniaturised, low impedance ratrace fabricated by microstrip line employing PPGM on MMIC

Using a novel microstrip line employing periodically perforated ground metal (PPGM), a highly miniaturised ratrace with a low port impedance of 10.6 /spl Omega/ was developed for K/Ka band monolithic microwave integrated circuit (MMIC) applications. Its size was 0.375 mm/sup 2/ on GaAs substrate, which was 9.3% of the one fabricated by conventional microstrip line. The ratrace exhibited good RF performance from 20 to 30 GHz.     

A K-band bi-phase modulator MMIC for UWB application

A 24-GHz-band, three-dimensional microwave monolithic integrated circuit (MMIC) bi-phase modulator, that is a combination of an active 0//spl pi/ splitter and a SPDT switch, is proposed and demonstrated. Comparing conventional K-band bi-phase modulators, this modulator is broadband, significantly MMIC compatible, and shrinks its chip area. A fabricated bi-phase modulator exhibits an area of 1.0/spl times/0.7mm/sup 2/ and a 1-dB bandwidth of nearly 10GHz. The SPDT switch is optimized in control-gate's time constant so that a very clear bi-phase modulated waveform can be generated from 1Gbps PN code. The insertion loss and the phase imbalance are 6.4 dB+/-0.6 dB and within 10/spl deg/, respectively, between 22GHz and 32GHz.     

K-band 3-D MMIC low noise amplifier and mixer using TFMS lines with ground slit

Three-dimensional (3-D) microwave monolithic integrated circuit (MMIC) technology, that incorporates slits in the ground metal, was applied to K-band low noise amplifier (LNA) and I/Q mixer to provide a low cost solution for various K-band receivers such as for P-to-P radio, WLAN, and UWB sensors. The LNA incorporates a quasicoplanar stub in the input-matching network, improving the noise figure by 1 dB. This low-noise amplifier (LNA) exhibits a noise figure of 2.5 dB with an associated gain of 16 dB and an area of 0.75/spl times/0.65 mm/sup 2/. The I/Q resistive mixer incorporates a broadside 3-dB coupler with a 22-/spl mu/m-wide slit in the ground metal beneath the coupled thin-film micro-strip (TFMS) lines (patent pending). The insertion loss of the 3 dB coupler is 0.75 dB. The I/Q mixer exhibits a conversion loss of less than 14 dB at 0.1-2.0GHz IF frequencies for 2-dBm local input power. These LNA and mixer potentially make it easier to integrate receiver functions in a die.     

BCB-bridged distributed wideband SPST switch using 0.25-/spl mu/m In/sub 0.5/Al/sub 0.5/As--In/sub 0.5/Ga/sub 0.5/As metamorphic HEMTs

In/sub 0.5/Al/sub 0.5/As--In/sub 0.5/Ga/sub 0.5/As metamorphic high-electron mobility transistor (mHEMT) dc-30 GHz distributed single-pole-single through (SPST) switches were designed and fabricated using the low-/spl kappa/ benzocyclobutene (BCB) bridged technology. The current gain cutoff frequency, and the electron transit time of In/sub 0.5/Al/sub 0.5/As--In/sub 0.5/Ga/sub 0.5/As mHEMTs have been investigated. By analyzing the extrinsic total delay time, the effective velocity of electrons can be estimated, and the average velocity is 2.3/spl times/10/sup 7/cm/s. The dc-30 GHz distributed wideband SPST switch exhibits an insertion loss of less than 5.5 dB, and an isolation larger than 30 dB, which is the first demonstration of the high-isolation of InAlAs-InGaAs mHEMTs monolithic switch. As to the power performance, this switch can handle the power up to 12 dBm at 2.4 GHz. After over 250 h of 85-85 (temperature =85/spl deg/C, humidity =85%) environmental evaluation, this BCB passivated and bridged microwave and monolithic integrated circuit switch demonstrates reliable RF characteristics without any significant performance change, which proves that this process using the low-/spl kappa/ BCB layer is attractive for millimeter-wave circuit applications.     

Low-power InP/GaAsSb/InP DHBT cascode transimpedance amplifier with GBP/P/sub dc/ of 7.2 GHz/mW

A low-power high gain-bandwidth monolithic cascode transimpedance amplifier using novel InP/GaAsSb/InP DHBT technology was investigated. The amplifier exhibited state-of-the-art performance of 17.3 dB gain, 12 GHz bandwidth, 55 dB/spl Omega/ transimpedance, and a corresponding gain-bandwidth of 6.7 THz/spl Omega/ while consuming only 12.2 mW DC power. It also achieved good gain-bandwidth-product per DC power figure-of-merit (GBP/P/sub dc/) of 7.2 GHz/mW     

A 20-GHz low-noise amplifier with active balun in a 0.25-/spl mu/m SiGe BICMOS technology

A 20-GHz low-noise amplifier (LNA) with an active balun fabricated in a 0.25-/spl mu/m SiGe BICMOS (f/sub t/=47 GHz) technology was presented by the authors in 2004. The LNA achieves close to 7 dB of gain and a noise figure of 4.9 dB with all ports simultaneously matched to 50 /spl Omega/ with better than -16 dB of return loss. The amplifier is highly linear with an IP/sub 1dB/ of 0 dBm and IIP/sub 3/ of 9 dBm, while consuming 14 mA of quiescent current from a 3.3-V rail, with temperature-compensated biasing. To the authors' knowledge, the LNA delivers the lowest reported noise figure and highest linearity for a silicon implementation of a combined active balun and LNA at 20 GHz, and is the first implementation of an active balun with an LC degenerated emitter-coupled pair. Here we expand on that work, with an analysis of the balun operation and noise optimization of the design.     

Internally matched, ultralow DC power consumption CMOS amplifier for L-band personal communications

An internally matched, extremely low operation voltage amplifier monolithic microwave integrated circuit (MMIC) has been implemented in a 0.35-/spl mu/m silicon-on-insulator (SOI) complementary metal oxide semiconductor (CMOS) technology for L-band personal communications. At 1.6 GHz the MMIC amplifier has a gain of 6.4 dB and a noise figure of 4.8 dB at a drain voltage of 0.6 V and a current of 2 mA. The MMIC amplifier exhibits a Gain/Power quotient as high as 5.33 dB/mW, which we believe is the highest recorded for Si CMOS MMIC technology.     

Beyond G-band: a 235 GHz InP MMIC amplifier

We present results on an InP monolithic millimeter-wave integrated circuit (MMIC) amplifier having 10-dB gain at 235GHz. We designed this circuit and fabricated the chip in Northrop Grumman Space Technology's (NGST) 0.07-/spl mu/m InP high electron mobility transistor (HEMT) process. Using a WR3 (220-325GHz) waveguide vector network analyzer system interfaced to waveguide wafer probes, we measured this chip on-wafer for S-parameters. To our knowledge, this is the first time a WR3 waveguide on-wafer measurement system has been used to measure gain in a MMIC amplifier above 230GHz.     

Attenuation mechanisms of aluminum millimeter-wave coplanar waveguides on silicon

The loss mechanisms of silicon coplanar waveguides (CPW) with aluminum metallization are investigated up to 40 GHz. Three main parts contribute to the attenuation of coplanar waveguides (CPWs): the frequency-dependent conductor losses of the metallization, frequency-independent substrate losses, and the specifically investigated bias-dependent interface losses caused by free charges at the Si-SiO/sub 2/ interface. The minimum losses found in 50-/spl Omega/ CPWs with 45-/spl mu/m signal line width were 0.19 db/mm at 10 GHz and 0.33 dB/mm at 40 GHz. High-purity silicon from a float zone (FZ) process was used as substrate. Substrates with lower purity from a Czochralski (CZ) process (resistivity 50-100 /spl Omega/cm) resulted in somewhat higher (0.2-0.3 dB/mm) losses for the same CPW geometry.     

Low-loss coplanar waveguides interconnects on low-resistivity silicon substrate

This paper describes fabrication, characterization and simulation of low-loss coplanar waveguide (CPW) interconnects on low-resistivity silicon substrate. The fabrication of CPWs is low-temperature (below 250/spl deg/C) and incorporates a spin-on low-k dielectric benzocyclobutene (BCB) and self-aligned electroplating of copper. The performance of CPWs is evaluated by high-frequency characterization and EM simulation. CPWs with different line width (W) and line spacing (S) are investigated and compared. Using a BCB layer as thick as 20 /spl mu/m, CPW fabricated on a low-resistivity silicon substrate exhibits an insertion loss of 3 dB/cm at 30 GHz.     

K-band HBT and HEMT monolithic active phase shifters using vector sum method

Two monolithic 3-bit active phase shifters using the vector sum method to K-band frequencies are reported in this paper. They are separately implemented using commercial 6-in GaAs HBT and high electron-mobility transistor (HEMT) monolithic-microwave integrated-circuit (MMIC) foundry processes. The MMIC HBT active phase shifter demonstrates an average gain of 8.87 dB and a maximum phase error of 11/spl deg/ at 18 GHz, while the HEMT phase shifter has 3.85-dB average measured gain with 11/spl deg/ maximum phase error at 20 GHz. The 20-GHz operation frequency of this HEMT MMIC is the highest among all the reported active phase shifters. The analysis for gain deviation and phase error of the active phase shifter using the vector sum method due to the individual variable gain amplifiers is also presented. The theoretical analysis can predict the measured minimum root-mean-square phase error 4.7/spl deg/ within 1/spl deg/ accuracy.     

Noise analysis of a photoreceiver using a P-I-N and GaAs HBT distributed amplifier combination

A noise analysis for a common-collector-cascode traveling wave HBT preamplifier is developed. The photoreceiver, consisting of a P-I-N and GaAs HBT MMIC distributed amplifier, was implemented using Nortel's f/sub T/=70 GHz GaAs HBT process, is the first to have a P-I-N mounted on the MMIC chip. The P-I-N preamplifier, having a measured bandwidth of 22 GHz, displayed a measured average equivalent input noise current density of 24 pA//spl radic/Hz. Good agreement was obtained between the predicted and measured noise performance.     

Simple K-band MMIC VCO utilizing a miniaturized hairpin resonator and a three-terminal p-HEMT varactor with low phase noise and high output power properties

Presents a fully monolithic K-band MMIC voltage-controlled oscillator (VCO) implemented by using a 0.25 /spl mu/m AlGaAs/InGaAs pseudomorphic HEMT (p-HEMT) technology. The use of a half-wavelength miniaturized hairpin-shaped resonator and a three-terminal p-HEMT varactor was effective in reducing the chip size and simplifying fabrication processes of the microwave MMIC VCO without impairing the performance of the circuit. The VCO provides a typical output power of 11.5 dBm at 20.8 GHz and a free-running phase noise of -82 dBc/Hz at 100 kHz offset and -95 dBc/Hz at 1 MHz offset. It also shows a tuning range of 70 MHz with little reduction in output power and high yield properties. The chip size of the MMIC VCO is 1.5 /spl times/ 2.0 mm/sup 2/.     

Millimeter-wave-band amplifier and mixer MMICs using a broad-band45° power divider/combiner

This paper demonstrates millimeter-wave-band amplifier and mixer monolithic microwave integrated circuits (MMIC's) using a broad-band 45° power divider/combiner. At first, we propose a broad-band 45° power divider/combiner, which combines a Wilkinson divider/combiner, 45° delay line, and 90° short stub. A coupling loss of 4.0±0.2 dB and a return loss and an isolation of more than 19 dB with 45±1° phase difference was obtained from 17 to 22 GHz for the fabricated K-band MMIC 45° power divider/combiner. Next, a parallel amplifier using the broad-band 45° power divider/combiner, which can be used in a power-combining circuit configuration requiring no isolator, is shown. Comparing the transmitter intermodulation generated in the parallel amplifier using the broad-band 45° power divider/combiner and that generated in the one using the conventional type, the broad-band suppression effect was confirmed. Finally, an application of the broad-band 45° power divider/combiner to a single-sideband (SSB) subharmonically pumped (SHP) mixer requiring no IF switch is shown. In an RF frequency range from 22.89 to 26.39 GHz, the fabricated K-band MMIC mixer achieved (for up-conversion) the good results of more than -13-dB conversion gain and more than 24-dB image-rejection ratio. These contribute significantly to the miniaturization of millimeter-wave communication equipment     

Microwave CMOS traveling wave amplifiers: performance and temperature effects

A monolithically integrated five-stage traveling wave amplifier (TWA) with a single n-MOSFET in each gain cell was designed, fabricated and tested in low-cost, standard 0.18 /spl mu/m CMOS technology. Coplanar waveguides (CPW) replace the large area spiral inductors or coplanar strip-lines. A gain of 10 dB at 1 GHz and a unity-gain bandwidth of 12 GHz was measured for the TWA at a gate bias of V/sub GS/=1.2 V and a drain bias of V/sub DS/=1.8 V. The effects of temperature on its gain, phase and stability have been investigated, and are reported for the first time for a CMOS TWA.     

Microwave CMOS traveling wave amplifiers: performance and temperature effects

A monolithically integrated five-stage traveling wave amplifier (TWA) with a single n-MOSFET in each gain cell was designed, fabricated and tested in low-cost, standard 0.18 /spl mu/m CMOS technology. Coplanar waveguides (CPW) replace the large area spiral inductors or coplanar strip-lines. A gain of 10 dB at 1 GHz and a unity-gain bandwidth of 12 GHz was measured for the TWA at a gate bias of V/sub GS/=1.2 V and a drain bias of V/sub DS/=1.8 V. The effects of temperature on its gain, phase and stability have been investigated, and are reported for the first time for a CMOS TWA.