Hexagonal boron nitride(h-BN)films are synthesized by dual temperature zone low-pressure chemical vapor deposition(LPCVD)through using a single ammonia borane precursor on non-catalytic c-plane Al_(2)O_(3)substrates.T...Hexagonal boron nitride(h-BN)films are synthesized by dual temperature zone low-pressure chemical vapor deposition(LPCVD)through using a single ammonia borane precursor on non-catalytic c-plane Al_(2)O_(3)substrates.The grown films are confirmed to be h-BN films by various characterization methods.Meanwhile,the growth rates and crystal quality of h-BN films at different positions in the dual temperature zone are studied.It is found that the growth rates and crystal quality of the h-BN films at different positions on the substrate are significantly different.The growth rates of the h-BN thin films show their decreasing trends with the rearward position,while the crystal quality is improved.This work provides an experimental basis for the preparation of large area wafer thick h-BN films by LPCVD.展开更多
A GaN-based pin neutron detector with a 6LiF conversion layer was fabricated, and can be used to detect thermal neutrons. Measurement of the electrical characteristic of the GaN-based pin neutron detector showed that ...A GaN-based pin neutron detector with a 6LiF conversion layer was fabricated, and can be used to detect thermal neutrons. Measurement of the electrical characteristic of the GaN-based pin neutron detector showed that the reverse leakage current of the neutron detector was reduced significantly after deposition of a 6LiF conversion layer on the detector surface. The thermal neutrons used in this experiment were obtained from an 241Am-Be fast neutron source after being moderated by 100-mm-thick high-density polyethylene. The experimental results show that the detector with 16.9-μm thick 6LiF achieved a maximum neutron detection efficiency of 1.9% at a reverse bias of 0 V, which is less than the theoretical detection efficiency of 4.1% calculated for our GaN neutron detectors.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.61964001)the Key Research and Development Program of Jiangxi Province,China(Grant No.20212BBG73012)+3 种基金the Natural Science Foundation of Jiangxi Province,China(Grant No.20192BAB207033)the Key Scientific Research Projects of Henan Higher Education Institutions,China(Grant No.22A490001)the State Key Laboratory of Particle Detection and Electronics,China(Grant No.SKLPDE-KF-2019)the Foundation of Engineering Research Center of Nuclear Technology Application(East China Institute of Technology)(Grant No.HJSJYB2021-4)。
文摘Hexagonal boron nitride(h-BN)films are synthesized by dual temperature zone low-pressure chemical vapor deposition(LPCVD)through using a single ammonia borane precursor on non-catalytic c-plane Al_(2)O_(3)substrates.The grown films are confirmed to be h-BN films by various characterization methods.Meanwhile,the growth rates and crystal quality of h-BN films at different positions in the dual temperature zone are studied.It is found that the growth rates and crystal quality of the h-BN films at different positions on the substrate are significantly different.The growth rates of the h-BN thin films show their decreasing trends with the rearward position,while the crystal quality is improved.This work provides an experimental basis for the preparation of large area wafer thick h-BN films by LPCVD.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61964001 and 61961001)the State Key Laboratory of Particle Detection and Electronics(Grant No.SKLPDE-KF-2019)+2 种基金the Natural Science Foundation of Jiangxi Province,China(Grant Nos.20192BAB207033 and 20181BAB202026)the Foundation of State Key Laboratory Breeding Base of Nuclear Resources and Environment(East China Institute of Technology)(Grant No.NRE1515)the Jiangxi Provincial Postdoctoral Science Foundation,China(Grant No.2018KY31).
文摘A GaN-based pin neutron detector with a 6LiF conversion layer was fabricated, and can be used to detect thermal neutrons. Measurement of the electrical characteristic of the GaN-based pin neutron detector showed that the reverse leakage current of the neutron detector was reduced significantly after deposition of a 6LiF conversion layer on the detector surface. The thermal neutrons used in this experiment were obtained from an 241Am-Be fast neutron source after being moderated by 100-mm-thick high-density polyethylene. The experimental results show that the detector with 16.9-μm thick 6LiF achieved a maximum neutron detection efficiency of 1.9% at a reverse bias of 0 V, which is less than the theoretical detection efficiency of 4.1% calculated for our GaN neutron detectors.