Journal of Crystal Growth, Vol.221, 722-729, 2000
InAlAs/InGaAs/InP heterostructures for RTD and HBT device applications grown by LP-MOVPE using non-gaseous sources
We report on the applicability of a fully non-gaseous source (ngs) configuration for MOVPE growth of InAlAs/InGaAs/InP heterostructures. The ngs configuration is based on TBAs/TBP/TMAs as group-V precursors and DitBuSi/CBr4 as dopant sources. Conventional group-III metalorganics and nitrogen-carrier gas are used. InAlAs/InGaAs RTD layer structures combined with carbon-doped InP/InGaAs HBT layers are characterized in detail by HRXRD measurements and simulations. The InAlAs layers exhibit n-type background concentration of n = 1.5 x 10(16) cm(-3) N = 1.7 x 10(17) cm(-3) determined by Hall and CV-measurements, respectively. Abrupt InAlAs/InGaAs heterojunction interfaces are deduced from the X-ray characterization. Fabricated RTDs exhibit a high peak current density of S-p > 1 x 10(5) A/cm(2) and a highly symmetric I-V characteristics. The RTD/HBT combination devices exhibit state-of-the-art device performance like a DC-current gain of B > 100 and a transit frequency of f(T) = 39GHz.