Platinum diffusion in InAlAs was investigated utilizing a PtTiPtAu gate contact on an In0.52 Al0.48 As In0.53 Ga0.47 AsInP high-electron-mobility transistor (HEMT) structure. Capacitance-voltage measurements on large gate field-effect transistors and high-resolution cross-sectional transmission electron microscopy enabled the measurement of Pt diffusion depth with nanometer-scale accuracy. A continuous increase in Pt diffusion depth was observed at an annealing temperature of 250 °C with increasing time. After a 40 min anneal, a diffusion depth of 8 nm was measured. Such a deep Pt diffusion in a HEMT structure not only changes device parameters but also constitutes a serious reliability problem during device operation.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)