GaAs tip and wedge-shaped field emitter arrays were fabricated by a wet etching technique on a (100) GaAs substrate. Two chemical solutions whose compositions were chosen for their isotropy features were investigated : HCl:H2O2:H2O (40:4:1) and HF:HNO3:H2O (1:1:2). When progressively polarized and after a working period of stabilization, the GaAs tip or wedge arrays are found to supply a stable emission current, with fluctuations not exceeding 3% over some hours. The analysis of the surface before emission shows the presence of a thin oxide layer which is suggested to act as a passivation layer.