ABSTRACTWe present the fabrication of side-illuminated p-i-n photodiode. This is suitable for passive integration on the planar lightwave circuit (PLC), which is able to make the low-cost packages. Epitaxial structures have two main layers, diode layer and waveguide layer. It was determined by beam propagation method (BPM) simulation. To get a high responsivity and reliability, each layer must be etched. The alignment tolerances were tested. We carried out some experiments on various methods and several devices were satisfactory for the optical communication system at 1.3- and 1.55 micrometer wavelengths.