Second harmonic generation (SHG) in birefringent GaAs/Al2O3 waveguides, using femtosecond fundamental pulses at 2.01 μm, was demonstrated. A Ti:sapphire pumped femtosecond periodically poled lithium niobate optical parametric oscillator was used as the optical source. The OPO provided idler pulses with duration of ∼200 fs at 90 MHz repetition rate tunable over a range of 1.8-2.1 μm at an average power of ∼50 mW. An average SHG power of ∼650 μW was generated with an input power of ∼50mW, corresponding to an overall external efficiency of 1.3%.