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DOE OSTI · 2222983

Temperature Dependence of Low‐Frequency Noise Characteristics of NiO x /β‐Ga 2 O 3 p–n Heterojunction Diodes

Ghosh, Subhajit [Univ. of California, Los Angeles, CA (United States); Univ. of California, Riverside, CA (United States)] (ORCID:0000000273505953)·Mudiyanselage, Dinusha Herath [Arizona State Univ., Tempe, AZ (United States)] (ORCID:0000000186119296)·Kargar, Fariborz [Univ. of California, Los Angeles, CA (United States); Univ. of California, Riverside, CA (United States)] (ORCID:0000000321922023)·Zhao, Yuji [Rice Univ., Houston, TX (United States)] (ORCID:0000000191994159)·Fu, Houqiang [Arizona State Univ., Tempe, AZ (United States)] (ORCID:0000000211258328)·Balandin, Alexander A. [Univ. of California, Los Angeles, CA (United States); Univ. of California, Riverside, CA (United States)] (ORCID:0000000299447894)
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Abstract

Temperature dependence of the low-frequency electronic noise in NiO x /β-Ga 2 O 3 p–n heterojunction diodes is reported. The noise spectral density is of the 1/f-type near room temperature but shows signatures of Lorentzian components at elevated temperatures and at higher current levels (f is the frequency). It is observed that there is an intriguing non-monotonic dependence of the noise on temperature near T = 380 K. The Raman spectroscopy of the device structure suggests material changes, which results in reduced noise above this temperature. The normalized noise spectral density in such diodes is determined to be on the order of 10 −14 cm 2 Hz −1 (f = 10 Hz) at 0.1 A cm −2 current density. In terms of the noise level, NiO x /β-Ga 2 O 3 p–n diodes perform excellently for new technology and occupy an intermediate position among devices of various designs implemented with different ultra-wide-bandgap semiconductors. The obtained results are important for understanding the electronic properties of NiO x /β-Ga 2 O 3 heterojunctions and contribute to the development of noise spectroscopy as the quality assessment tool for new electronic materials and device technologies.

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1/f noise36 MATERIALS SCIENCEflicker noisep-n diodeswide bandgap semiconductors

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Ghosh, Subhajit [Univ. of California, Los Angeles, CA (United States); Univ. of California, Riverside, CA (United States)] (ORCID:0000000273505953), Mudiyanselage, Dinusha Herath [Arizona State Univ., Tempe, AZ (United States)] (ORCID:0000000186119296), Kargar, Fariborz [Univ. of California, Los Angeles, CA (United States); Univ. of California, Riverside, CA (United States)] (ORCID:0000000321922023), Zhao, Yuji [Rice Univ., Houston, TX (United States)] (ORCID:0000000191994159), Fu, Houqiang [Arizona State Univ., Tempe, AZ (United States)] (ORCID:0000000211258328), Balandin, Alexander A. [Univ. of California, Los Angeles, CA (United States); Univ. of California, Riverside, CA (United States)] (ORCID:0000000299447894). 2023-11-29. Temperature Dependence of Low‐Frequency Noise Characteristics of NiO x /β‐Ga 2 O 3 p–n Heterojunction Diodes. https://doi.org/10.1002/aelm.202300501

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