US 9,812,566 B1
LDMOS device having a low angle sloped oxide
Sagy Levy, Zichron-Yaakov (IL); Sharon Levin, Haifa (IL); and David Mistele, Haifa (IL)
Assigned to TOWER SEMICONDUCTORS LTD., Migdal Haemeq (IL)
Filed by Tower Semiconductor Ltd., Midgal Haemek (IL)
Filed on Jul. 3, 2016, as Appl. No. 15/201,460.
Int. Cl. H01L 29/00 (2006.01); H01L 29/78 (2006.01); H01L 29/66 (2006.01); H01L 29/10 (2006.01); H01L 29/08 (2006.01); H01L 21/265 (2006.01)
CPC H01L 29/7816 (2013.01) [H01L 21/26566 (2013.01); H01L 29/0882 (2013.01); H01L 29/1095 (2013.01); H01L 29/66681 (2013.01)] 18 Claims
OG exemplary drawing
 
9. A method for manufacturing a laterally diffused metal oxide semiconductor (LDMOS) device, the method comprises:
fabricating a substrate and an oxide region; wherein the oxide region comprises a bottom surface; wherein the oxide region further comprises a first sloped surface and a second sloped surface; wherein the bottom surface is formed above the substrate; wherein a first angle between the first sloped surface and the bottom surface does not exceed twenty degrees; and wherein a second angle between the second sloped surface and the bottom surface of the oxide region does not exceed twenty degrees;
forming an elongated trench above the substrate; wherein the elongated trench passes through the oxide region;
applying a selective implant process that is followed by a spike anneal implant activation stage thereby forming a drain within the substrate; wherein the drain is positioned between a right and left drift regions; and
fabricating, within the elongated trench, a conductive drain contact that is electrically coupled to the drain.