Depth distributions of 300‐keV protons implanted inn‐type GaAs and characteristics of the associated damage in the crystalline material have been obtained. Range profiles of the implanted1H ions as a function of substrate implantation temperature have been determined using secondary ion mass spectrometry for fluences of 5×1014and 5×1015cm−2. The projected range for the protons was approximately 2.7 &mgr;m for the room temperature implants, but a significant rearrangement of the1H atoms occurred during elevated temperature implantation. While cross‐sectional transmission electron microscopy showed no evidence of crystal damage in as‐implanted wafers, plan‐view measurements revealed platelike damage structures in the surface region (< 1&mgr;m).