Growth of AlInAs using low-oxygen-content metalorganic precursors and application to HEMT structures

An AlInAs layer and high electron mobility transistor (HEMT) structures were grown using low-oxygen-content metalorganic precursors by metalorganic vapor phase epitaxy (MOVPE). The oxygen concentration in the AlInAs layer measured by secondary ion mass spectrometry (SIMS) was 7 /spl times/ 10/sup 15/ cm/sup -3/. Moreover, the mobility and sheet carrier concentrations of the AlInAs/InP HEMT structure in which a 2.5 /spl mu/m-thick AlInAs buffer layer was inserted to reduce the diffusion of impurities from the substrate surface, were 5,500 cm/sup 2//Vs and 1.0 /spl times/ 10/sup 12/ cm/sup -2/ at 300 K, and 110,000 cm/sup 2//Vs and 8.7 /spl times/ 10/sup 11/ cm/sup -2/ at 77 K, respectively. For the AlInAs/GaInAs HEMT structure with the same buffer layer, mobility and sheet carrier concentrations were 12,000 cm/sup 2//Vs and 1.2 /spl times/ 10/sup 12/ cm/sup -2/ at 300 K, and 92,000 cm/sup 2//Vs and 1.2 /spl times/ 10/sup 12/ cm/sup -2/ at 77 K, respectively.