Capacitance-voltage fitting algorithm for doping profile characterisation of Mesa Diodes using MATLAB

In this study, a capacitance-voltage fitting algorithm was developed using four region approximations and fitted against three GaAs mesa diodes. Doping and electric field profile measured and fitted are presented using MATLAB based programming. Results of 4-regions approach gave a better fitting in all the diodes compared to 3-regions approximation. It also showed good approximation to the mesa diodes measured C-V by using higher number of approximated region

Effects on electrical characteristics of commercially available Si and GaAs diodes exposed to Californium-252 radiation

The aim of this research is to investigate the effects of neutron irradiation using Cf-252 neutron source on different types of commercially available Si and GaAs diodes. Pre and post irradiation effects are compared by analyzing their respective forward bias (FB) and reverse bias (RB) current-voltage (I-V) characteristics. It was discovered that, at low neutron dose of up to 178.63mSv, the electrical characteristics of silicon diodes improved as indicated by a reduction in FB and RB leakage current, ideality factor and series resistance. However, GaAs diodes show a significant leakage current increment in RB which is interpreted as being due to damage displacement

Electrical properties of neutron-irradiated silicon and GaAs commercial diodes

Neutron radiation testing was performed on silicon and GaAs diodes to investigate changes in the device parameters after neutron exposure. Californium-252 source was used to irradiate these diodes up to total dose of 1117.87mSv. The effects of nuclear radiation on the forward and reverse current-voltage (I-V) characteristics of Silicon and GaAs diodes were studied at room temperature. It was found that the magnitudes of forward bias electrical characteristics were in most instances unaffected by irradiation in both materials. The increments in TSKS5400S GaAs infrared emitting diode reverse currents were large after irradiation. These changes were interpreted as effects of displacement damage generating generation-recombination currents due to defects created. However, reverse bias (RB) characteristics of 1N4148 silicon diodes showed decrement in dark current. This is attributed to the type of diodes used

Effects of neutron on reverse bias characteristics of commercially available SI and gaas diodes

This study investigates the effects of neutron radiation on reverse bias characteristics of commercial silicon and gallium arsenide diodes. Reverse bias current-voltage and capacitance-voltage characteristics of the diodes were measured at room temperature before and after irradiation. The diodes were irradiated using Pneumatic Transfer System facility at PUSPATI TRIGA reactor with neutron fluences up to (6.038 3.067) x1012 n /cm2.s for a period of 1, 3 and 5 minutes. The results showed an increase in leakage current for all diodes which may be due to the existence of neutron-induced displacement defects introduced into the semiconductor lattice. The doping concentration of gallium arsenide diodes is observed to decrease after irradiation which is attributed to carrier removal process

Effects on the Forward Bias Characteristics of Neutron Irradiated Si and GaAs Diodes

The aim of this study is to investigate the effects on forward bias characteristics of neutron radiation on various commercially available silicon and GaAs diodes. The diodes were irradiated using the Pneumatic Transfer System (PTS) facility in Malaysian Nuclear Agency with neutron fluences up to 1012 neutron/cm2.s for an exposure time of 1, 3 and 5 min. The Forward Bias (FB) current-voltage (I-V) characteristics and doping profiles of the diodes were recorded before and after irradiation. It is observed that the FB leakage current of the silicon and GaAs diodes increases after irradiation. The increase in leakage current is interpreted as being due to an increase of generation-recombination traps created in the band gap after radiation. The doping concentration of GaAs diodes in FB is observed to decrease while the series resistance increases after irradiation which may be attributed to changes in doping concentration due to carrier removal by the defects produced

Effects of high neutron fluence on the electrical characteristics of InAs quantum dot structures

The use of InAs quantum dots (QDs) in a well (DWELL) structure as a medium to minimize propagation of neutron induced defects is presented. The DWELL samples and GaAs based commercial diodes were radiated with thermal neutron under maximum fluence of 1.4×1016 neutron/cm2. Based on the current-voltage (I-V) characteristics, it was discovered that the forward bias (FB) leakage current for both devices decreased as an effect of increment in series resistance. In reverse bias (RB), there is significant decrement in leakage current of DWELL samples in the order of 2 orders of magnitude. The RB leakage current of GaAs diode showed similar response as in FB. However, the QD based structures showed less defects compared to the GaAs based diode