A method of forming a fine pattern begins with providing a c-plane hexagonal semiconductor crystal. A mask having a predetermined pattern is formed on the semiconductor crystal. The semiconductor crystal is dry-etched by using the mask to form a first fine pattern on the semiconductor crystal. The semiconductor crystal including the first fine pattern is wet-etched to expand the first fine pattern in a horizontal direction to form a second fine pattern. The second fine pattern obtained in the wet-etching the semiconductor crystal has a bottom surface and a sidewall that have unique crystal planes, respectively. The present fine-pattern forming process can be advantageously applied to a semiconductor light emitting device, particularly, to a phonic crystal structure required to have fine patterns or a structure using a surface plasmon resonance principle.