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Title: On electrical analysis of Al-rich p-AlGaN films for III-nitride UV light emitters
Abstract In this work, an alternative scheme to estimate the resistivity and ionization energy of Al-rich p-AlGaN epitaxial films is developed using two large-area ohmic contacts. Accordingly, the resistivities measured using current–voltage measurements were observed to corroborate the Hall measurements in the Van der Pauw configuration. A free hole concentration of ∼1.5 × 10 17 cm −3 and low ionization energy of ∼65 meV in Mg-doped Al 0.7 Ga 0.3 N films is demonstrated. Nearly an order of magnitude lower hydrogen concentration than Mg in the as-grown AlGaN films is thought to reduce the Mg passivation and enable higher hole concentrations in Al-rich p-AlGaN films, compared to p-GaN films. The alternate methodology proposed in this work is expected to provide a simpler pathway to evaluate the electrical characteristics of Al-rich p-AlGaN films for future III-nitride ultraviolet light emitters.  more » « less
Award ID(s):
1916800 1653383
PAR ID:
10318726
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Semiconductor Science and Technology
Volume:
37
Issue:
1
ISSN:
0268-1242
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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