Improved performance of non-annealed ohmic-recess metamorphic high electron mobility transistor

An interesting In_0.5Al_0.5As/In_0.5Ga_0.5As metamorphic high electron mobility transistor with non-annealed ohmic-recess (NAOR) technique is fabricated and studied. Experimentally, the parasitic resistance is substantially reduced. The used NAOR technique shows benefits of the absence of thermal treatment (non-annealed) for ohmic contact. Compared with the traditional structure, both the DC and the RF performance is significantly improved. From experimental results, the studied 1 m gate length with NAOR technique exhibits breakdown voltage of 22.93 (16.89) V, drain saturation current of 327 (299) mA/mm and parasitic resistance of 1.67 (2.02) Omega-mm at 300 (500) K. the unity current gain cutoff frequency f _t and maximum oscillation frequency f _max are 20.5 and 62.3 GHz at 300 K.