Influence of Thermal and Fast Neutron Irradiation on dc Electrical Performances of AlGaN/GaN Transistors

Abstract

The influence of thermal neutron irradiation and fast neutron irradiation on the electrical properties of AlGaN/GaN HEMTs is investigated. An increase in the drain current and a decrease in the access resistances are observed when devices are irradiated with a thermalized neutrons fluence of while no evolution is observed with the same fluence of fast neutrons. However, the same phenomenon is observed when the fast neutron fluence is higher . AlGaN/GaN heterojunctions are analyzed by gamma spectroscopy after thermalized or fast neutron irradiations to understand the physical mechanisms induced by irradiations. In fact, we have shown that the improvement of electrical properties of devices after thermal neutrons irradiation is linked to a Ga-Ge transmutation effect. Moreover, the evolution of the drain current and access resistance when the AlGaN/GaN heterojunctions are irradiated by fast neutrons can be induced by N vacancies creation and/or a change of the strain state of the layers and/or Ga-Ge transmutation effect.

Development of a fast neutron spectrometer based on a plastic fiber array

“…However, classic fast neutron detectors often work at low energy range below several MeV, and most of the classic detector can hardly measure the energy, the direction, and the emission time of the original neutrons. So, new methods must be used to get above-mentioned information of neutrons [1][2][3][4][5][6][7][8][9][10].…”

Low‐Fluence Neutron Irradiation Effects on AlGaN/GaN HEMTs

“…= n e kT q (11) As we calculated, the ideality factor of the device irradiated with the fluence of 4.5 × 10 13 cm −2 has no obvious changes. The n values of the preirradiation and post-irradiation devices are 1.5 and 1.53, respectively.…”

“…[ 10 ] In these applications (e.g., satellite communication systems, nuclear industry, and military defense), devices are usually subjected to both electromagnetic and particles radiation, including electrons, heavy ions, protons, neutrons, and γ‐rays. [ 11 ] Thus, it is very necessary to explore the reliability of GaN‐based devices in these radiation environments. According to the basic interaction model between irradiation particles and devices, irradiation effects can be divided into ionization damage and displacement damage.…”

Analysis of Trapping Effects on AlInN/GaN High Electron Mobility Transistors with Pulsed Electrical Measurements Under Visible and Infrared Illumination

“…It can be done immediately after the fabrication of the devices or electrical stresses under operational conditions and/or in a radiation environment. [7,[11][12][13][14][15][16][17] Thus, the characterization of trapping or detrapping phenomena can be investigated by various techniques such as capacitance deep-level transient spectroscopy, [18] drain-current deep-level transient spectroscopy, [9] gate and drain lag measurements, [19] double pulse measurements, [20] photoionization spectroscopy, [21] electroluminescence techniques, [22] and deep-level optical spectroscopy. [23] All these techniques can provide information on the trapping effects responsible for the electrical performance degradation of GaN-based devices.…”