Vapor phase epitaxial gallium arsenide (GaAs) layers, with lower compensation ratios than any reported heretofore, have been reproducibly grown by the Ga/H2/AsCl3method. One of these samples has been studied extensively by electrical measurements and shows an acceptor concentration of (2.0±0.7)×1013cm−3, and a compensation rate ofNA/ND=0.06±0.02. These numbers are supported by magnetophotothermal spectroscopy and photoluminescence measurements. The preparation involves growth on [211A] substrates, and a pregrowth bakeout of the Ga source, which results in a significantly lower Zn acceptor concentration in the layer. These results have important implications for various compensation mechanisms which have been proposed for GaAs.