Injection electroluminescence from diffused diodes of gallium‐aluminum arsenide has been investigated. These diodes were prepared from material deposited epitaxially from the liquid state onto oriented gallium arsenide substrates. Diffused diodes emitting radiation at wavelengths as short as 7150 Å have been prepared from material estimated to contain 0.28 mole fraction of AlAs. Microscopic examination has shown that the recombination radiation originates within approximately 1 &mgr; of the junction region. Data on measurements of wavelength and efficiency vs aluminum melt concentration are presented. On the basis of the measured emission wavelengths, the mole fractions of AlAs in the deposited gallium‐aluminum arsenide layers are given.