Exposure and etching time optimalization in GaAs grating fabrication

The details of the fabrication of diffraction gratings in photoresist and GaAs, are reported. Optimum exposures, resulting in uniform, deep gratings in photoresist and GaAs have been found. Also, different etching times have been examined in order to define the best conditions for GaAs grating fabrication. Furthermore, the behaviour of the GaAs grating is shown in comparison with the adequate photoresist mask.