Hetero-epitaxy of L_g=0.13-μm metamorphic AlInAs/GaInAs HEMT on Si substrates by MOCVD for logic applications

In this work, a hetero-epitaxial Al_0.49In_0.51As/Ga_0.47In_0.53As metamorphic high electron mobility transistor (mHEMT) grown by metal–organic chemical vapor deposition (MOCVD) on p-type silicon substrate has been successfully demonstrated. A novel AlGaAs/AlAs period multiple quantum well (MQW) composite buffer scheme is developed to effectively tune the leakage current from the buffer layer. The quantized room-temperature Hall mobility of the two-dimensional electron gas (2DEG) is larger than 7800 cm²/V·s, with an average sheet carrier density of 4.6×10¹² cm^-2. Two-stage electron beam (EB) lithography technology by a JBX-6300 e-beam lithography system is developed to realize a 0.13-μm mHEMT device on Si substrate. A maximum transconductance G_m of up to 854 mS/mm is achieved, and is comparable to that of mHEMT technology on GaAs substrate with the same dimension. The f_T and f_max are 135 GHz and 120 GHz, respectively.