Study of electric field enhanced emission rates of an electron trap in n-type GaN grown by hydride vapor phase epitaxy
2010 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 108, no 10Article in journal (Refereed) Published
Electric field-enhanced emission of electrons from a deep level defect in GaN grown by hydride vapor phase epitaxy has been studied. Using the field dependent mode of conventional deep level transient spectroscopy (DLTS), several frequency scans were performed keeping applied electric field (12.8-31.4 MV/m) and sample temperature (300-360 K) constant. Arrhenius plots of the resultant data yielded an activation energy of the electron trap E ranging from E-c -0.48 +/- 0.02 eV to E-c-0.35 +/- 0.02 eV, respectively. The extrapolation of the as-measured field dependent data (activation energy) revealed the zero-field emission energy (pure thermal activation energy) of the trap to be 0.55 +/- 0.02 eV. Various theoretical models were applied to justify the field-enhanced emission of the carriers from the trap. Eventually it was found that the Poole-Frenkel model associated with a square well potential of radius r=4.8 nm was consistent with the experimental data, and, as a result, the trap is attributed to a charged impurity. Earlier, qualitative measurements like current-voltage (I-V) and capacitance-voltage (C-V) measurements were performed, and screening parameters of the device were extracted to ascertain the reliability of DLTS data.
Place, publisher, year, edition, pages
American Institute of Physics , 2010. Vol. 108, no 10
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-63959DOI: 10.1063/1.3499669ISI: 000285005000073OAI: oai:DiVA.org:liu-63959DiVA: diva2:384496
H. Ashraf, M. Imran Arshad, Sadia Muniza Faraz, Qamar Ul Wahab, P. R. Hageman and M. Asghar, Study of electric field enhanced emission rates of an electron trap in n-type GaN grown by hydride vapor phase epitaxy, 2010, Journal of Applied Physics, (108), 10, 103708.
Copyright: American Institute of Physics