Thin undoped layers of GaAs grown directly on GaAs semi‐insulating substrates via liquid phase epitaxy (LPE) are shown to exhibit excellent buffering characteristics. Interfacial drift mobilities are shown to be much higher for the multilayer structures employing the thin buffer layer as compared with single‐layer structures. GaAs metal semiconductor field‐effect transistors (MESFET) fabricated on these LPE multilayer structures are shown to exhibit excellent rf characteristics. Best results include a noise figure of 1.87 dB with an associated gain of 10.6 dB at 12 GHz and a noise figure of 2.4 dB with an associated gain of 6.3 dB at 18 GHz.