Bandwidth Improvement of MMIC Single-Pole-Double-Throw Passive HEMT Switches with Radial Stubs in Impedance-Transformation Networks

In this paper, we propose a new configuration for improving the isolation bandwidth of MMIC single-pole-double-throw (SPDT) passive high-electron-mobility transistor (HEMT) switches operating at millimeter frequency range. While the conventional configuration adopted open-stub loading for compensation of the off-state capacitance, radial stubs were introduced in our approach to improve the operational bandwidth of the SPDT switch. Implemented in 0.15 m GaAs pHEMT technology, the proposed configuration exhibited a measured insertion loss of less than 2.5 dB with better than 30 dB isolation level over the frequency range from 33 GHz to 44 GHz. In terms of the bandwidth of operation, the proposed configuration achieved a fractional bandwidth of 28.5% compared to that of 12.3% for the conventional approach. Such superior bandwidth performance is mainly attributed to the less frequency dependent nature of the radial stubs.

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Full integrated process to manufacture RF-MEMS and MMICs on GaN/Si substrate

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078710000474 ◽

2010 ◽

Vol 2 (3-4) ◽

pp. 333-339 ◽

Cited By ~ 4

Author(s):

Flavia Crispoldi ◽

Alessio Pantellini ◽

Simone Lavanga ◽

Antonio Nanni ◽

Paolo Romanini ◽

...

Keyword(s):

Insertion Loss ◽

Rf Mems ◽

Noise Figure ◽

High Electron Mobility Transistor ◽

Low Noise ◽

High Electron ◽

Mems Devices ◽

Frequency Range ◽

Gan Hemt ◽

Better Than

Radio Frequency Micro-Electro-Mechanical System (RF-MEMS) represents a feasible solution to obtain very low power dissipation and insertion loss, very high isolation and linearity switch with respect to “solid state” technologies. In this paper, we demonstrate the full integration of RF-MEMS switches in the GaN-HEMT (Gallium Nitride/High Electron Mobility Transistor) fabrication line to develop RF-MEMS devices and LNA-MMIC (Low Noise Amplifier/Monolithic Microwave Integrated Circuit) prototype simultaneously in the same GaN wafer. In particular, two different coplanar wave (CPW) LNAs and a series of discrete RF-MEMS in ohmic-series and capacitive-shunt configuration have been fabricated. RF-MEMS performances reveal an insertion loss and isolation better than 1 and 15 dB, respectively, in the frequency range 20–50 GHz in the case of pure capacitive shunt switches and in the frequency range 5–35 GHz for the ohmic-series switches. Moreover, the GaN HEMT device shows an Fmax of about 38 GHz and a power density of 6.5 W/mm, while for the best LNA-MMIC we have obtained gain better than 12 dB at 6–10 GHz with a noise figure of circa 4 dB, demonstrating the integration achievability.

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Gate Capacitance and Off-State Characteristics of E-Mode p-GaN Gate AlGaN/GaN High-Electron-Mobility Transistors After Gate Stress Bias

Journal of Electronic Materials ◽

10.1007/s11664-020-08691-w ◽

2021 ◽

Author(s):

Yu-Chen Lai ◽

Yi-Nan Zhong ◽

Ming-Yan Tsai ◽

Yue-Ming Hsin

Keyword(s):

Leakage Current ◽

Electron Mobility ◽

High Electron Mobility Transistors ◽

High Electron ◽

High Electron Mobility ◽

Gate Capacitance ◽

Enhancement Mode ◽

Electron Mobility Transistors ◽

Higher Power ◽

State Capacitance

AbstractThis study investigated the gate capacitance and off-state characteristics of 650-V enhancement-mode p-GaN gate AlGaN/GaN high-electron-mobility transistors after various degrees of gate stress bias. A significant change was observed in the on-state capacitance when the gate stress bias was greater than 6 V. The corresponding threshold voltage exhibited a positive shift at low gate stress and a negative shift when the gate stress was greater than 6 V, which agreed with the shift observation from the I–V measurement. Moreover, the off-state leakage current increased significantly after the gate stress exceeded 6 V during the off-state characterization although the devices could be biased up to 1000 V without breakdown. The increase in the off-state leakage current would lead to higher power loss.

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