Electron-spin resonance of transparent conductive oxide β-Ga2O3

Yamaga, M.; Tsuzuki, Hiromi; Takano, Sayumi; Vı́llora, Encarnación G.; Shimamura, Kiyoshi

doi:10.1016/j.jnoncrysol.2011.11.033

Cited by 12 publications

(3 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Prior reports have suggested several deep acceptors which could explain our data. For example, Yamaga et al have proposed a compensation mechanism where an interstitial O forms a Frenkel pair with an O vacancy (O i -V O pair), that traps excess donor electrons (see [56] and references therein). However, the SIMS data in figure 3(b), as well as CL obtained from reference commercial Fe-doped (010) Ga 2 O 3 substrates, suggest that the reduced CL emission could have originated from the outdiffusion of Fe in these samples, as the 3 kV accelerating voltage on the CL gun limits the probing depth to about 100 nm below the surface.…”

Section: Resultsmentioning

confidence: 99%

Structural and electronic properties of Si- and Sn-doped (−201) β-Ga₂O₃ annealed in nitrogen and oxygen atmospheres

Tadjer

Freitas

Culbertson

et al. 2020

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

Single crystal (−201) β-Ga2O3 substrates doped with Si and Sn have been thermally annealed in N2 and O2 atmospheres. Structural and electrical properties evaluation was performed via a number of experimental methods in order to quantify the effects of the doping and annealing ambient on the properties of these samples. All samples annealed in O2 exhibited significantly lower carrier concentration, as determined by capacitance–voltage measurements. Schottky barrier diodes exhibited excellent rectification when the Ga2O3 was annealed in N2, and significantly lower forward current using O2-annealed Ga2O3 substrates. Deep level transient spectroscopy revealed four deep trap levels with activation energies in the range of 0.40–1.07 eV. Electron spin resonance showed a decrease in shallow donor concentration, and cathodoluminescence spectroscopy revealed nearly two orders of magnitude lower emission intensity in O2-annealed Ga2O3 samples. Raman spectroscopy revealed a carrier concentration dependent Raman mode around 254 cm−1 observed only when the final anneal of (−201) β-Ga2O3 was not done in O2. Secondary ion mass spectroscopy measurements revealed diffusion of unintentional Fe towards the surface of the (−201) Ga2O3 samples after annealing in O2. Depth resolved positron annihilation spectroscopy showed an increased density of vacancy defects in the bulk region of O2-annealed Ga2O3 substrates.

show abstract

Section: Resultsmentioning

confidence: 99%

Structural and electronic properties of Si- and Sn-doped (−201) β-Ga₂O₃ annealed in nitrogen and oxygen atmospheres

Tadjer

Freitas

Culbertson

et al. 2020

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

show abstract

“…One tempting speculation is oxygen vacancy, which is shown by first-principle calculations 25,26) to be of low formation energy and located near the conduction band (∼1.5 eV below E C ). However, with several extrinsic impurities observed at low ppm level in glow discharge mass spectrometry analysis of unintentionally doped Ga 2 O 3 substrates by edge-defined film-fed growth, [27][28][29] it is also possible that this defect level is extrinsic in origin. Recently, Ingebrigtsen et al used a comprehensive scheme to demonstrate 30) that this deep level is more likely due to Fe impurity 31) than due to intrinsic point defects.…”

Section: Discussionmentioning

confidence: 99%

β-Ga₂O₃ defect study by steady-state capacitance spectroscopy

Huang

López

Paul

et al. 2018

Jpn. J. Appl. Phys.

View full text Add to dashboard Cite

We use steady-state capacitance measurement originally intended for capacitance–voltage experiment to observe and characterize the electrical properties of deep defects in β-Ga2O3 semiconductors. We detect a deep level located 0.81 eV below the conduction band edge with a concentration of 1.2 × 1016 cm−3 and a capture cross-section of 1.1 × 10−14 cm2, making it potentially influential in determining the performance of β-Ga2O3 based power electronic and optoelectronic devices. This deep level may dominate the thermal activation of off-state drain current in β-Ga2O3 transistors at high temperatures and, together with another shallower level at 0.13 eV, may substantially lower the breakdown voltage in Schottky diodes.

show abstract

“…Later EPR studies suggested that this donor is related to the O vacancy 18 or the Frenkel pair of VO and the O interstitial, VO-Oi. 19 Hall-effect measurements gave an estimated donor ionization energy in the range of 16-30 meV for conducting β-Ga2O3. 20,21 However, hybrid functional calculations suggested VO to be deep donors and, therefore, cannot be responsible for the n-type conductivity in UID materials.…”

Section: Introductionmentioning

confidence: 99%

Electronic properties of the residual donor in unintentionally doped β-Ga2O3

Són

Goto

Nomura

et al. 2016

Journal of Applied Physics

View full text Add to dashboard Cite

Electron paramagnetic resonance (EPR) was used to study the donor that is responsible for the n-type conductivity in unintentionally doped (UID) β-Ga2O3 substrates. We show that in asgrown material, the donor requires high temperature annealing to be activated. In partly activated material with the donor concentration in the 10 16 cm -3 range or lower, the donor is found to behave as a negative-U center (often called a DX center) with the negative charge

show abstract

Electron-spin resonance of transparent conductive oxide β-Ga2O3

Cited by 12 publications

References 15 publications

Structural and electronic properties of Si- and Sn-doped (−201) β-Ga₂O₃ annealed in nitrogen and oxygen atmospheres

Structural and electronic properties of Si- and Sn-doped (−201) β-Ga₂O₃ annealed in nitrogen and oxygen atmospheres

β-Ga₂O₃ defect study by steady-state capacitance spectroscopy

Electronic properties of the residual donor in unintentionally doped β-Ga2O3

Contact Info

Product

Resources

About

Electron-spin resonance of transparent conductive oxide β-Ga2O3

Cited by 12 publications

References 15 publications

Structural and electronic properties of Si- and Sn-doped (−201) β-Ga2O3 annealed in nitrogen and oxygen atmospheres

Structural and electronic properties of Si- and Sn-doped (−201) β-Ga2O3 annealed in nitrogen and oxygen atmospheres

β-Ga2O3 defect study by steady-state capacitance spectroscopy

Electronic properties of the residual donor in unintentionally doped β-Ga2O3

Contact Info

Product

Resources

About

Structural and electronic properties of Si- and Sn-doped (−201) β-Ga₂O₃ annealed in nitrogen and oxygen atmospheres

Structural and electronic properties of Si- and Sn-doped (−201) β-Ga₂O₃ annealed in nitrogen and oxygen atmospheres

β-Ga₂O₃ defect study by steady-state capacitance spectroscopy