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Integration of a photon source into the AlGaN/GaN high election mobility transistor (HEMT) platform will realize the functionality of on-chip optical pumping of deep electron traps which suppress the dynamic performances of power HEMTs. Here, we report a Schottky-on-heterojunction light-emitting diode (SoH-LED) realized on the p-doping-free lateral AlGaN/GaN heterostructure. A physical mode based on hot electron induced surface states impact ionization was proposed to explain the hole generation and injection processes in this p-doping-free SoH-LED. Since the SoH-LED shares identical epitaxial structures with HEMT, integration of SoH-LED and HEMT requires no additional epi-layers during the wafer growth and minimum process modification during device fabrication. The SoH-LED structure was seamlessly integrated into the HEMT platform as an on-chip photon source. Experiment results showed that the SoH-LED photons can effectively assist the electron de-trapping processes from both of the surface and bulk deep traps, demonstrating the feasibility of using on-chip generated photons to improve the dynamic performances of AlGaN/GaN power HEMTs. [ABSTRACT FROM AUTHOR]

The degradation of transient OFF-state leakage current in AlGaN/GaN HEMTs induced by ON-state gate overdrive was observed and studied. The OFF-state leakage current increases significantly with a pre- ON-state gate overdrive. It takes more than 30 s for the leakage current decay to its equilibrium level in dark. The decay processes follow a stretched-exponential law. We propose that this degradation corresponds to the persistent photoconductivity of GaN buffer induced by the electroluminescence during the Schottky gate overdrive. Both the ON-state gate overdrive bias and duration dependences of the OFF-states leakage degradation were studied. This work indicates that gate-protection is necessary to preserve low OFF-state leakage current and improve device reliability. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Monolithic integrated 1.9-GHz low noise amplifier (LNA) using 1 μm-gate high-linearity and low noise composite-channel Al0.3Ga0.7N/Al0.05Ga0.95N/GaN HEMT (CC-HEMT) device is designed, fabricated and characterized. The LNA exhibits a noise figure of 1.3 dB, an associated gain of 17 dB, an input return loss of -5.5 dB and an output return loss of -15 dB at 1.9 GHz. The IIP3 and IIP5 of the LNA are 15 and 12 dBm at 1.9 GHz. The LNA with 1 × 100 μm2 device shows high-dynamic range with decent gain and noise figure. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1360–1362, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22459 [ABSTRACT FROM AUTHOR]