The liquid phase epitaxial (LPE) growth method has been successfully used to fabricate GaAs microwave device structures. General material requirements for the GaAs microwave devices currently of interest are reviewed in this paper. An LPE technology based on a multiple-well graphite slider boat, utilized for growth of multilayer structures, is described. Selection of dopants and control of unwanted background impurities are discussed in detail. Doping profiles and rf performance data on Gunn and Avalanche devices are presented to define the state-of-the-art in GaAs LPE capability.