Abstract: A method of forming micro-trench isolation regions with a separation of 0.20 .mu.m to 0.35 .mu.m in the fabrication of semiconductor devices involves forming an silicon dioxide layer on select locations of a semiconductor substrate and depositing a polysilicon layer onto the silicon dioxide layer. A layer of photoresist is then deposited over select areas of the polysilicon layer and patterned to form micro-trench isolation regions of widths between about 0.2 .mu.m to about 0.5 .mu.m and aspect ratio of between about 2:1 to about 7:1. Thereafter, the isolation regions are etched for a time and pressure sufficient to form micro-trenches in the substrate surface. The micro-trenches will generally have a width ranging from about 1000 .ANG. to about 3500 .ANG. and depth ranging from about 500 .ANG. to about 5000 .ANG.. The layer of photoresist is then removed to expose the polysilicon layer and a channel stop implant is deposited and aligned with the micro-trenches.