We present two different methods to pattern the band gap of dilute nitrides in their growth plane by exploiting the unique capability of H to passivate N in these materials. By deposition of metallic masks on and subsequent H irradiation of GaAs 1-x N x, we artificially create zones of the crystal having the band gap of untreated GaAs 1-XNX well surrounded by GaAs-like barriers. Alternatively, by focusing an energetic e--beam on the surface of hydrogenated GaAs 1-x N x we displace H atoms from their N passivation sites, thus ...