US 12,170,311 B1
Manufacturing method for a power MOSFET with gate-source ESD diode structure
Wan-Yu Kai, New Taipei (TW); Chia-Wei Hu, New Taipei (TW); and Ta-Chuan Kuo, New Taipei (TW)
Assigned to Diodes Incorporated, Plano, TX (US)
Filed by Diodes Incorporated, Plano, TX (US)
Filed on Jul. 2, 2024, as Appl. No. 18/762,560.
Application 18/762,560 is a division of application No. 18/416,776, filed on Jan. 18, 2024.
Int. Cl. H01L 29/06 (2006.01); H01L 27/02 (2006.01); H01L 29/423 (2006.01); H01L 29/78 (2006.01)
CPC H01L 29/063 (2013.01) [H01L 27/0255 (2013.01); H01L 29/4236 (2013.01); H01L 29/7813 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method comprising:
growing an epitaxial layer over a substrate;
forming a plurality of gates in the epitaxial layer;
forming a breakdown voltage enhancement and leakage prevention structure in the epitaxial layer, comprising a body ring structure formed through an implantation process, wherein the body ring structure is a concentric ring structure;
forming a source and a body region in the epitaxial layer;
forming an interlayer dielectric layer over the epitaxial layer;
forming a gate-source Electrostatic Discharge (ESD) diode and a plurality of trenches in the interlayer dielectric layer;
forming a plurality of p+ regions at bottoms of respective trenches;
performing a metal deposition process to fill the plurality of trenches to form a plurality of source contact plugs and a gate contact plug;
forming a source contact and a gate contact through an etching process;
connecting the source contact to the source and a first terminal of the gate-source ESD diode structure;
coupling the gate contact to the plurality of gates;
connecting the gate contact to a second terminal of the gate-source ESD diode structure; and
forming a drain contact underneath the substrate.