Material and technology developments of the totally sputtering- made p GaN diodes for cost-effective power electronics

摘要

Mg-doped GaN (Mg-GaN) films have been deposited on Si (100) substrates by radio-frequency reactive sputtering technique with single cermet targets. The targets can be made by hot pressing the mixture of metallic Ga and Mg powders and ceramic GaN powder. X-ray diffraction results showed that Mg-GaN films had a wurtzite structure with a preferential nonpolar m - (1010) growth plane. Mg-GaN with 10.2 % Mg has transformed into p-type conductivity and has the carrier concentration of 9.37 × 10~(16) cm~(-3), the highest mobility of 345 cm~2 V~(-1) s~(-1) and the highest conductivity of 3.23 S cm~(-1). The band gap of Mg-GaN films retrieved from the absorption spectra is 2.93-3.06 eV. Furthermore, we have also fabricated a totally sputtering-made and cost-effective GaN diode with the ideality factors of 5.0 and 4.9 for the as-deposited and the annealed, respectively.