Au-Doped Indium Tin Oxide Ohmic Contacts to p-Type GaN

Abstract

Indium tin oxide (ITO) thin films doped with Au, Ni, or Pt (3.5 at.% to 10.5 at.%) were deposited on p-GaN epilayers (Mg $4 9 10 19 cm À3 ) using direct-current (DC) sputter codeposition. It was found that undoped ITO contacts to p-GaN exhibited leaky Schottky behavior, whereas the incorporation of a small amount of Au (3.5 at.% to 10.5 at.%) significantly improved their ohmic characteristics. Compared with standard Ni/ITO contacts, the Au-doped ITO contacts had a similar specific contact resistance in the low 10 À2 X cm À2 range, but were more stable above 600°C and more transparent at blue wavelengths. These results provide support for the use of Au-doped ITO ohmic contact to p-type GaN in high-brightness blue light-emitting diodes.

Epitaxial Zinc Stannate (Zn2SnO4) Thin Film for Solar Cells

“…Zinc stannate (Zn 2 SnO 4 ) is a transparent conducting oxide that has high electron mobility, attractive electrical and optical properties, and low visible absorption, so it is suitable for a wide range of applications, such as flat-panel displays, gas sensors, light-emitting diodes, and lithium ion batteries. − It has also been used as working electrodes in dye-sensitized solar cells (DSSC). − In DSSCs, Zn 2 SnO 4 can be used in either host materials or buffer layers . The applicability of Zn 2 SnO 4 in solar cells should be evaluated, because they need a wide band gap semiconductor that has long electron diffusion. − These applications require a well-crystallized and phase-pure Zn 2 SnO 4 , but Zn 2 SnO 4 undergoes phase separation and evaporation, so these traits are difficult to obtain …”

Effect of Different Compositions of Mixed Metal Oxides (Zinc Oxide and Tin Oxide) on Structural and Optical Properties for the Application of Window Layers in Solar Cells

“…Transparent conducting oxides (TCOs) have numerous applications, including flat-panel displays, solar cells, gas sensors, and light-emitting diodes [1][2][3][4][5][6][7]. Because of their exceptional thermal and chemical stability, zinc-tin-oxide materials have recently gained much interest [1][2][3][4][5].…”