We investigated non-alloy Ohmic contact to p-type GaN using Mg-doped InGaN contact layer. The thickness and In mole fraction of the p-type InGaN were varied from 2 to 15 nm and from 0.14 to 0.23, respectively. Strained InGaN contact layers are effective in reducing the contact resistance. The lowest specific contact resistance of 1.1 × 10-6 Ω cm2 was obtained using a contact layer of 2 nm thick strained In0.19Ga0.81N. The mechanism for the lower contact resistance is ascribed to enhanced tunneling transport due to the large polarization-induced band bending at the surface as well as the high hole concentration in p-type InGaN.
|Number of pages||4|
|Journal||Physica Status Solidi (A) Applied Research|
|Publication status||Published - 2001 Nov|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics