MOS WITH RECESSED LIGHTLY-DOPED DRAIN

摘要

LDD regions are provided with high implant energy in devices with reduced thickness poly-silicon layers and source/drain junctions. Embodiments include forming an oxide layer on a substrate surface, forming a poly-silicon layer over the oxide layer, forming first and second trenches through the oxide and poly-silicon layers and below the substrate surface, defining a gate region therebetween, implanting a dopant in a LDD region through the first and second trenches, forming spacers on opposite side surfaces of the gate region and extending into the first and second trenches, and implanting a dopant in a source/drain region below each of the first and second trenches.

主权项

1. A device comprising:
a substrate having a surface; a gate region on the substrate surface; a recess in the substrate on each side of the gate region; a source/drain region in the substrate, below each recess; and a spacer on each side of the gate region and extending down into the recess.