CMOS structure and latch-up preventing method of same
AssigneeUnited Microelectronics Corp.
InventorsFang-Mei Chao, Ming-I Chen, Ying-Ko Chin, Yi-Chiao Wang
Life of this patent
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Abstract
A CMOS structure includes a PMOS portion and an NMOS portion isolated from each other via a P-well region disposed next to the PMOS portion and an N-well region disposed between the P-well region and the NMOS portion, an insulation layer overlying at least the N-well region, and a pad structure disposed over the N-well region. The pad structure further includes: a pad body disposed on the insulation layer; and at least one contact plug penetrating through the insulation layer, having one end coupled to the pad body and the other end coupled to a contact zone in the N-well region; wherein the contact zone is interfaced with the N-well region with P-type dopants.
Claims12
A CMOS structure, comprising a PMOS portion and an NMOS portion isolated from each other via a P-well region disposed next to the PMOS portion and an N-well region disposed next to the P-well region and the NMOS portion respectively, an insulation layer overlying at least the N-well region, and a pad structure disposed over the N-well region, the pad structure further comprising:
- a pad body disposed on the insulation layer;
- and
- at least one contact plug penetrating through the insulation layer, having one end coupled to the pad body and the other end coupled to a contact zone in the N-well region;
- wherein the contact zone interfaces the N-well region with P-type dopants, the contact zone includes an inner dopant area formed with N-type dopants and an outer dopant area formed with the P-type dopants.
A method for preventing a CMOS IC from a latch-up effect, the CMOS IC having a base structure including a PMOS portion and an NMOS portion isolated from each other via a P-well region disposed next to the PMOS portion and an N-well region disposed next to the P-well region and the NMOS portion respectively, the method comprising:
- forming an insulation layer overlying the base structure;
- creating at least one contact hole penetrating through the insulation layer;
- performing an implantation process to provide P-type dopants as an outer area of a contact zone for interfacing an inner area of the contact zone with the N-well region, wherein the inner area of the contact zone is previously implanted with N-type dopants;
- forming at least one contact plug in the at least one contact hole, the at least one contact plug having one end coupled to the contact zone;
- and
- forming a pad body on the insulation layer, coupled to the other end of the at least one contact plug.
Dependencies are inferred from the claim text.