A steady-state photocapacitance (SSPC) setup directly connected to the beam line of a MeV ion implanter is utilized to study primary intrinsic defects in $\beta$-Ga${}_2$O${}_3$ generated by He implantation at cryogenic temperatures (). At low temperatures, the migration of defects is suppressed, and hence the generation of primary intrinsic defects is expected to prevail. SSPC measurements reveal defect-related optical transitions in HVPE-grown $\beta$-Ga${}_2$O${}_3$ thin-films with onset energies at 1.3 ($T_1$), 1.7 ($T_2$), 1.9 ($T_3$), 2.6 ($T_4$), 3.7 ($T_5$) and ($T_6$). $T_2$, $T_4$, $T_5$ and $T_6$ were observed in as-received $\beta$-HVPE-grown Ga${}_2$O${}_3$ thin-films, whereby $T_2$ is only sporadically observed. The introduction rates for $T_3$, $T_4$ as well as $T_6$ indicate an origin related to primary intrinsic defects. Notably, $T_1$ and $T_3$ are only observed after He implantation at cryogenic temperatures. Hybrid-functional calculations were performed to estimate the optical absorption cross section spectra for the gallium (Ga${}_i$) and oxygen (O${}_i$) interstitials as well as the corresponding vacancies (V${}_{G}a$ and V${}_O$, respectively), and compared with the measured onsets for optical absorption found by SSPC measurements. Indeed, we tentatively assign $T_3$ to Ga${}_i$ and/or V${}_{G}aI$, while $T_4$ and $T_6$ are suggested to rather be related to V${}_{O}K$ (K = I, II, III) or V${}_{G}aII$. We further studied the kinetics of the defects created with He implantation by exposing the sample to room temperature. The kinetics observed for $T_3$ and $T_4$ further corroborate the assignment of the corresponding defect signatures.

中文翻译：

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β-Ga2O3中的主要本征缺陷及其电荷转移水平

直接连接到MeV离子注入机的束线的稳态光电容（SSPC）装置用于研究硅中的主要固有缺陷 $\beta$镓${}_2$Ø${}_3$在低温下植入氦气产生的（）。在低温下，缺陷的迁移得到抑制，因此，预期会产生主要的固有缺陷。SSPC测量揭示了HVPE生长的缺陷相关的光学跃迁$\beta$镓${}_2$Ø${}_3$ 能量为1.3（${Ť}_{\mathrm{1个}}$），1.7（${Ť}_2$），1.9（${Ť}_3$），2.6（${Ť}_4$），3.7（${Ť}_5$）和（${Ť}_6$）。 ${Ť}_2$， ${Ť}_4$， ${Ť}_5$ 和 ${Ť}_6$ 被观察到的 $\beta$-HVPE生长的Ga${}_2$Ø${}_3$ 薄膜 ${Ť}_2$仅偶尔观察到。的引进率${Ť}_3$， ${Ť}_4$ 以及 ${Ť}_6$表示与主要内在缺陷有关的起源。值得注意的是${Ť}_{\mathrm{1个}}$ 和 ${Ť}_3$仅在低温下植入He后观察到。进行混合函数计算以估计镓（Ga${}_{\mathrm{一世}}$）和氧气（O${}_{\mathrm{一世}}$）插页式广告以及相应的空缺（V${}_G\mathrm{一种}$ 和V${}_{Ø}$），并与通过SSPC测量发现的光学吸收的测量起始点进行比较。确实，我们暂时分配${Ť}_3$ 到嘎${}_{\mathrm{一世}}$ 和/或V${}_G\mathrm{一种}\mathrm{一世}$，而 ${Ť}_4$ 和 ${Ť}_6$ 建议与V相关${}_{Ø}ķ$ （K = I，II，III）或V${}_G\mathrm{一种}\mathrm{一世}\mathrm{一世}$。我们通过将样品置于室温下，进一步研究了由He注入产生的缺陷的动力学。观察到的动力学${Ť}_3$ 和 ${Ť}_4$ 进一步证实了相应缺陷签名的分配。