Dec 19, 2014

Larger wafers boosting GaAs and InP electronics

The boom in the compound semiconductor industry was evident at both the GaAs MANTECH conference in Washington DC and the Indium Phosphide and Related Materials conference in Williamsburg, Virginia in May, with delegate and exhibitor numbers up by as much as 50% on last year. A key concern at both was supply of larger-diameter wafers — 6″ GaAs and 4″ InP — to meet demand for electronic devices.

Dec 1, 2014

Characterization of semi-polar GaN on GaAs substrates

Cubic GaN was grown on GaAs(0 0 1). The GaN layers were found to exhibit residual strain with a measured a-lattice parameter of 4.4990 Å. The GaN layers were grown on GaAs(1 1 0) forming cubic crystal structure with an a-lattice parameter of 4.4947 Å for the LT-GaN buffer layers and a hexagonal structure with an a-lattice parameter of 2.7463 Å and a c-lattice parameter of 5.5882 Å for the main GaN layers. Comparisons between the two GaAs substrate orientations, GaN on GaAs(1 1 0) showed a smoother surface (R  rms of 5.369 nm) than that on GaAs(0 0 1) (R  rms of 9.776 nm). It was shown by a TEM investigation that semi-polar GaN layers with low defect densities could be grown by MOCVD on GaAs(1 1 0) substrates. The TEM results indicated GaNView the MathML source//GaAs[1 1 0] and GaNView the MathML source//GaAs(1 1 0) crystal orientations.