Ju Yeon Hong

0.15 /spl mu/m gate length InAlAs/InGaAs power metamorphic HEMT on GaAs substrate with extremely low noise characteristics

The 0.15 /spl mu/m gate-length power metamorphic HEMTs (MHEMT) with wide head T-shaped gate has been fabricated and the DC, microwave, and noise performance of the device were characterized. The MHEMT device shows the DC output characteristics having an extrinsic transconductance of 740 mS/mm and a threshold voltage of -0.75 V. The f/sub T/ and f/sub max/ obtained for the 0.15 /spl mu/m /spl times/ 100 pm MHEMT device are 150 GHz and 240 GHz, respectively. The MHEMTs exhibit the minimum noise figure, NF/sub min/, of 0.79 dB and associated gain of 10.5 dB at 26 GHz. The NF/sub min/ measured at 40 GHz is 1.21 dB with associated gain of 6.41 dB. This noise data is the lowest value ever reported for power MHEMT devices with InGaAs channel of 53% In. The excellent noise characteristics might result from the low gate resistance due to the wide head T-shaped gate and the improved device performance.

A 77GHz automotive radar MMIC chip set fabricated by a 0.15/spl mu/m MHEMT technology

A MMIC chip set consisting of a power amplifier, a driver amplifier, low noise amplifier, and a frequency doubler has been developed for automotive radar systems at 77GHz. The chip set was fabricated using 0.15 /spl mu/m gate-length InGaAs/InAlAs/GaAs mHEMT process based on 4-inch substrate. The power amplifier demonstrated a measured small signal gain of over 20 dB from 76-77GHz with 15.5 dBm output power. The chip size is 2mm /spl times/ 2mm. The driver amplifier exhibited a gain of 23dB over a 76-77 GHz band with an output power of 13dBm. The chip size is 2.1mm /spl times/ 2mm. The low noise amplifier achieved a gain of 20 dB in a band between 76-77GHz with an output power of 10 dBm. The chip size is 2.2mm /spl times/ 2mm. The frequency doubler achieved an output power of -6 dBm at 76.5 GHz with a conversion gain of -16dB for an input power of 10 dBm and a 38.25 GHz input frequency. The chip size is 1.2 mm /spl times/ 1.2mm. This MMIC chip set is suitable for the 77 GHz automotive radar systems and related applications in W-band.

Low noise characteristics of double-doped In/sub 0.52/Al/sub 0.48/As/In/sub 0.53/Ga/sub 0.47/As power metamorphic HEMT on GaAs substrate with wide head T-shaped gate

The 0.2 /spl mu/m gate-length power MHEMTs with the wide head T-shaped gate are characterized for DC, microwave, and noise performance. The MHEMT device shows the DC output characteristics having an extrinsic transconductance of 700 mS/mm and a threshold voltage of -0.92 V. The f/sub T/ and f/sub max/ obtained for the 0.2 /spl mu/m /spl times/ 100 /spl mu/m MHEMT device are 120 GHz and 230 GHz, respectively. The MHEMTs exhibit the minimum noise figure, NF/sub min/, of 1.26 dB and associated gain of 8.6 dB at 30 GHz. The NF/sub min/ measured at 35 GHz is 1.45 dB with associated gain of 7.5 dB. This noise data is first reported for power MHEMT devices with InGaAs channel of 53% In. These excellent noise characteristics can be explained by the drastic reduction of gate resistance owing to the T-shaped gate with a wide head of about 1.2 /spl mu/m and the improved device performance.

Extremely Low Noise Characteristics of 0.15 µm Power Metamorphic High-Electron-Mobility Transistors

The DC and RF characteristics of a 0.15 µm GaAs power metamorphic high electron mobility transistor (MHEMT) have been investigated and consequently, 77-GHz-band-low-noise-amplifier (LNA) millimeter-wave monolithic integrated circuits (MMICs) were fabricated using the 0.15 µm power MHEMT device. The 0.15 ×100 µm2 MHEMT device showed a drain saturation current of 40.4 mA/mm, an extrinsic transconductance of 857 mS/mm, and a threshold voltage of -0.64 V. For the distributions of DC characteristics across a 100 mm wafer, the standard deviation of the threshold voltage and the maximum extrinsic transconductance were -0.64 ±0.03 V and 810 ±25 mS/mm, respectively. The obtained cutoff frequency and maximum frequency of oscillation were 141 and 243 GHz, respectively. The 8 ×50 µm2 MHEMT device showed a 33.2% PAE, an 18.1 dB power gain, and a 50.1 mW output power at 5.8 GHz. A very low minimum noise figure of 0.79 dB and an associated gain of 10.56 dB at 26 GHz were obtained for the 0.15 ×100 µm2 MHEMT with an indium content of 53% in the InGaAs channel. This excellent noise characteristic is attributed to the marked reduction of gate resistance by the T-shaped gate with a wide head and the improved device performance. The fabricated LNA MMIC using a 0.15 ×100 µm2 MHEMT device exhibited a small signal gain of 20 dB and a noise figure of 5.5 dB at a frequency range of 76 to 77 GHz.

DC and RF Characteristics of 60 nm T-gate MHEMTs with 53% Indium Channel

In this paper T-gate metamorphic high electron mobility transistors with 60 nm gate length has been developed using T-gate lithography process. Electron beam lithography was used to define 60 nm gate using ZEP single layer on SiN layer, which is used to fabricate structurally stable T-gate HEMTs. The SiN layer was then etched over 130% of the layer thickness for enhancing yield using reactive ion etching, followed by second electron beam lithography process. DC and RF performances of 60 nm T-gate MHEMTs were characterized.

0.15 /spl mu/m gate length MHEMT technology for 77 GHz automotive radar applications

The 0.15 /spl mu/m gate-length power metamorphic HEMTs (MHEMT) with wide head T-shaped gate has been fabricated and the DC, and microwave performance of the device were characterized. The MHEMT device shows the DC output characteristics having an extrinsic transconductance of 740 mS/mm and a threshold voltage of -0.75 V. The f/sub T/ and f/sub max/ obtained for the 0.15 /spl mu/m /spl times/ 100 /spl mu/m MHEMT device are 150 GHz and 240 GHz, respectively. A MMIC 77 GHz 3-stage amplifier is reported in this paper. This MMIC chip demonstrated a measured small signal gain of over 12 dB from 70 GHz to 79 GHz with 7 dBm output power at 1 dB compression. The maximum small signal gain is above 13.5 dB from 77 to 78 GHz. This chip is fabricated using 0.15 /spl mu/m MHEMT process based on 4-inch substrate. This MMIC chip size is 1.7 mm /spl times/ 2 mm. This MMIC amplifier chip is suitable for the 77 GHz automotive radar systems and related transmitter applications in W-band.

Characteristics of 80 nm T-Gate Metamorphic HEMTx with 60 % Indium Channel

The 80 nm T-gate metamorphic high electron mobility transistors (MHEMTs) with 60% indium channel have been fabricated and the DC, microwave, and uniformity of the device were characterized. The MHEMT device showed the DC characteristics having an extrinsic transconductance of 1150 mS/mm and a gate breakdown voltage of -6.2 V. The fT and fmax obtained for the 80 nm times 100 mum MHEMT device are 235 GHz and 290 GHz, respectively. The MHEMT exhibited uniform threshold voltage of -0.47 V with a standard deviation of 0.045 V across the wafer.

A W-band MMIC One-Chip Set for Automotive Radar Sensor by using a 0.15μm mHEMT Process

A monolithic microwave integrated circuit (MMIC) one-chip set consisting of a transmitter and an 8-stage low noise amplifier has been developed for automotive radar sensors at 77 GHz. The chip set was fabricated using a 0.15 mum gate-length InGaAs/InAlAs/GaAs metamorphic high electron mobility transistor (mHEMT) process based on a 4-inch substrate. The transmitter achieved an output power of 11 dBm at 76.5 GHz with a conversion gain of 6 dB for an input power of 5 dBm and a 38.25 GHz input frequency. The chip size is 5.1 mm times 2.2 mm. The 8-stage low noise amplifier exhibited a gain of 35 dB over a 76 to 77 GHz band with a noise figure of 6 dB. The chip size is 4.1 mm times 2.2 mm. This MMIC one-chip set is suitable for the 77 GHz automotive radar sensors and related applications in a W-band

Extremely low noise characteristics of 0.1/spl mu/m /spl Gamma/-gate power metamorphic HEMT on GaAs substrate

The 0.1 /spl mu/m /spl Gamma/-gate power metamorphic high electron mobility transistors (MHEMTs) has been fabricated and the DC, microwave, and noise performance of the device were characterized. The MHEMT device shows the DC output characteristics having an extrinsic transconductance of 830 mS/mm and a threshold voltage of /spl square/0.62 V. The f/sub T/ and f/sub max/ obtained for the 0.1 /spl mu/m/spl times/100 /spl mu/m MHEMT device are 165 GHz and 275 GHz, respectively. The MHEMTs exhibit the minimum noise figure, NF/sub min/, of 0.64 dB and associated gain of 12.4 dB at 26 GHz. The NF/sub min/ measured at 40 GHz is 1.1 dB with associated gain of 9.7 dB. This noise data is the lowest value ever reported for /spl Gamma/-gate power MHEMT devices with InGaAs channel of 53% In.