Wide-bandgap gallium oxide(Ga_(2)O_(3))is one of the most promising semiconductor materials for solar-blind(200 nm to 280 nm)photodetection.In its amorphous form,amorphous gallium oxide(a-Ga_(2)O_(3))maintains its int...Wide-bandgap gallium oxide(Ga_(2)O_(3))is one of the most promising semiconductor materials for solar-blind(200 nm to 280 nm)photodetection.In its amorphous form,amorphous gallium oxide(a-Ga_(2)O_(3))maintains its intrinsic optoelectronic properties while can be prepared at a low growth temperature,thus it is compatible with Si integrated circuits(ICs)technology.Herein,the a-Ga_(2)O_(3) film is directly deposited on pre-fabricated Au interdigital electrodes by plasma enhanced atomic layer deposition(PE-ALD)at a growth temperature of 250°C.The stoichiometric a-Ga_(2)O_(3) thin film with a low defect density is achieved owing to the mild PE-ALD condition.As a result,the fabricated Au/a-Ga_(2)O_(3)/Au photodetector shows a fast time response,high responsivity,and excellent wavelength selectivity for solar-blind photodetection.Furthermore,an ultra-thin MgO layer is deposited by PE-ALD to passivate the Au/a-Ga_(2)O_(3)/Au interface,resulting in the responsivity of 788 A/W(under 254 nm at 10 V),a 250-nm-to-400-nm rejection ratio of 9.2×10^(3),and the rise time and the decay time of 32 ms and 6 ms,respectively.These results demonstrate that the a-Ga_(2)O_(3) film grown by PE-ALD is a promising candidate for high-performance solar-blind photodetection and potentially can be integrated with Si ICs for commercial production.展开更多
A1GaN/GaN high electron-mobility transistors （HEMTs） with 5 nm A1N passivation by plasma en- hanced atomic layer deposition （PEALD） were fabricated, covered by 50 nm SiNx which was grown by plasma enhanced chemica...A1GaN/GaN high electron-mobility transistors （HEMTs） with 5 nm A1N passivation by plasma en- hanced atomic layer deposition （PEALD） were fabricated, covered by 50 nm SiNx which was grown by plasma enhanced chemical vapor deposition （PECVD）. With PEALD A1N passivation, current collapse was suppressed more effectively and the devices show better subthreshold characteristics. Moreover, the insertion of A1N increased the RF transconductance, which lead to a higher cut-off frequency. Temperature dependence of DC characteristics demonstrated that the degradations of drain current and maximum transconductance at elevated temperatures for the A1N/SiNx passivated devices were much smaller compared with the devices with SiNx passivation, indicating that PEALD A1N passivation can improve the high temperature operation of the A1GaN/GaN HEMTs.展开更多
基金This work was supported by the National Natural Science Foundation of China under Grant No.21872019 and the Innovation Group Project of Sichuan Province under Grant No.20CXTD0090This work was also partly supported by the Slovenian Research Agency under Grants No.P2-0412 and No.J2-2498 for A.Mavric and M.Valant,and No.Z1-3189 for N.Pastukhova。
文摘Wide-bandgap gallium oxide(Ga_(2)O_(3))is one of the most promising semiconductor materials for solar-blind(200 nm to 280 nm)photodetection.In its amorphous form,amorphous gallium oxide(a-Ga_(2)O_(3))maintains its intrinsic optoelectronic properties while can be prepared at a low growth temperature,thus it is compatible with Si integrated circuits(ICs)technology.Herein,the a-Ga_(2)O_(3) film is directly deposited on pre-fabricated Au interdigital electrodes by plasma enhanced atomic layer deposition(PE-ALD)at a growth temperature of 250°C.The stoichiometric a-Ga_(2)O_(3) thin film with a low defect density is achieved owing to the mild PE-ALD condition.As a result,the fabricated Au/a-Ga_(2)O_(3)/Au photodetector shows a fast time response,high responsivity,and excellent wavelength selectivity for solar-blind photodetection.Furthermore,an ultra-thin MgO layer is deposited by PE-ALD to passivate the Au/a-Ga_(2)O_(3)/Au interface,resulting in the responsivity of 788 A/W(under 254 nm at 10 V),a 250-nm-to-400-nm rejection ratio of 9.2×10^(3),and the rise time and the decay time of 32 ms and 6 ms,respectively.These results demonstrate that the a-Ga_(2)O_(3) film grown by PE-ALD is a promising candidate for high-performance solar-blind photodetection and potentially can be integrated with Si ICs for commercial production.
基金Project supported by the National Natural Science Foundation of China(No.60890192)
文摘A1GaN/GaN high electron-mobility transistors （HEMTs） with 5 nm A1N passivation by plasma en- hanced atomic layer deposition （PEALD） were fabricated, covered by 50 nm SiNx which was grown by plasma enhanced chemical vapor deposition （PECVD）. With PEALD A1N passivation, current collapse was suppressed more effectively and the devices show better subthreshold characteristics. Moreover, the insertion of A1N increased the RF transconductance, which lead to a higher cut-off frequency. Temperature dependence of DC characteristics demonstrated that the degradations of drain current and maximum transconductance at elevated temperatures for the A1N/SiNx passivated devices were much smaller compared with the devices with SiNx passivation, indicating that PEALD A1N passivation can improve the high temperature operation of the A1GaN/GaN HEMTs.
