Gaubas E, Čeponis T, Meškauskaite D, Mickevičius J, Pavlov J, Rumbauskas V, Grigonis R, Zajac M, Kucharski R
Institute of Photonics and Nanotechnology, Vilnius University, Sauletekio av. 3, LT-10257, Vilnius, Lithuania.
Laser centre, Vilnius University, Sauletekio av. 10, LT-10222, Vilnius, Lithuania.
Sci Rep. 2019 Feb 6;9(1):1473. doi: 10.1038/s41598-018-38138-6.
GaN-based structures are promising for production of radiation detectors and high-voltage high-frequency devices. Particle detectors made of GaN are beneficial as devices simultaneously generating of the optical and electrical signals. Photon-electron coupling cross-section is a parameter which relates radiation absorption and emission characteristics. On the other hand, photon-electron coupling cross-section together with photo-ionization energy are fingerprints of deep centres in material. In this work, the wafer fragments of the GaN grown by ammonothermal (AT) technology are studied to reveal the dominant defects introduced by growth procedures and reactor neutron irradiations in a wide range, 10-10 cm, of fluences. Several defects in the as-grown and irradiated material have been revealed by using the pulsed photo-ionization spectroscopy (PPIS) technique. The PPIS measurements were performed by combining femtosecond (40 fs) and nanosecond (4 ns) laser pulses emitted by optical parametric oscillators (OPO) to clarify the role of electron-phonon coupling. Variations of the operational characteristics of the tentative sensors, made of the AT GaN doped with Mg and Mn, under radiation damage by reactor neutrons have been considered.
基于氮化镓的结构在辐射探测器和高压高频器件的生产方面很有前景。由氮化镓制成的粒子探测器作为同时产生光信号和电信号的器件具有优势。光子 - 电子耦合截面是一个与辐射吸收和发射特性相关的参数。另一方面，光子 - 电子耦合截面与光电离能一起是材料中深能级中心的特征标志。在这项工作中，研究了通过氨热（AT）技术生长的氮化镓晶圆碎片，以揭示在10⁻¹⁰ 厘米的宽注量范围内生长过程和反应堆中子辐照引入的主要缺陷。通过使用脉冲光电离光谱（PPIS）技术揭示了生长态和辐照材料中的几种缺陷。PPIS测量是通过结合光学参量振荡器（OPO）发射的飞秒（40飞秒）和纳秒（4纳秒）激光脉冲来进行的，以阐明电子 - 声子耦合的作用。已经考虑了由掺杂镁和锰的AT氮化镓制成的试验性传感器在反应堆中子辐射损伤下的工作特性变化。
