Patent ID: 8101338

Claim:
A method of forming a micro pattern of a semiconductor device, the method comprising: forming a first photoresist layer and a second photoresist layer with different exposure types of resists, one of which is a positive resist and the other of which is a negative resist, over a semiconductor substrate on which an etch target layer is formed; forming second exposure regions in the second photoresist layer and forming first exposure regions in the first photoresist layer by performing an exposure process using one exposure mask, wherein the second exposure regions and the first exposure regions are formed at different energy levels; forming second photoresist patterns by developing the second photoresist layer, wherein each of the second photoresist patterns covers exposed regions of the first photoresist layer and has wider width than the covered exposed regions; forming first photoresist patterns by etching the first photoresist layer using an etching process employing the second photoresist patterns as an etch mask; forming auxiliary patterns by removing the exposed regions included in the first photoresist patterns using a development process; and etching the etch target layer by employing the auxiliary patterns.