CN-121985589-A - ESD protection device and method for manufacturing the same

CN121985589ACN 121985589 ACN121985589 ACN 121985589ACN-121985589-A

Abstract

The invention provides an ESD protection device and a preparation method of the ESD protection device, the ESD protection device comprises an N-type well region, a P-type well region and an N-type well region which are sequentially distributed along a first direction, wherein a first N-type heavily doped region and a first P-type heavily doped region which are adjacent along the first direction are arranged in the N-type well region, a second N-type heavily doped region and a second P-type heavily doped region which are distributed at intervals along the first direction are arranged in the P-type well region, a P-type shallow doped region which is adjacent to the P-type well region is also arranged in one N-type well region, any one of two connecting ends of an anode and two connecting ends of a cathode is connected with the surface of one first N-type heavily doped region and the surface of one first P-type heavily doped region of a corresponding ESD protection structure, and any one connecting end of two connecting ends of a conductive connecting structure is connected with the surface of one corresponding second P-type heavily doped region and the surface of one second N-type heavily doped region.

Inventors

Guo Furao
WU ZHONGRUI
CHEN MIN
OU XINHUA
YUAN QIONG

Assignees

上海芯导电子科技股份有限公司

Dates

Publication Date: 20260505
Application Date: 20251226

Claims (10)

1. An ESD protection device, comprising: A substrate; The two electrostatic protection structures are positioned in the substrate, each electrostatic protection structure comprises a P-type well region positioned in the substrate, two N-type well regions respectively positioned in the two sides of the P-type well region along a first direction, a first N-type heavily doped region and a first P-type heavily doped region which are adjacent along the first direction are arranged in the N-type well region, a second N-type heavily doped region and a second P-type heavily doped region which are distributed at intervals along the first direction are arranged in the P-type well region, a P-type shallow doped region is also arranged in one N-type well region in the 2N-type well regions, the P-type shallow doped region is positioned between the second N-type heavily doped region and the first P-type heavily doped region in one N-type well region, the P-type shallow doped region and the first P-type heavily doped region in one N-type well region are distributed at intervals and extend to at least to the junction of the P-type region and the first N-type heavily doped region, and the P-type well region extends to the surface of the other N-type well region along the first direction; The electrostatic protection structure comprises an anode and a cathode, wherein any one of two connecting ends of the anode is connected with the surface of a first N-type heavily doped region and the surface of a first P-type heavily doped region of one corresponding N-type well region of the electrostatic protection structure, and any one of two connecting ends of the cathode is connected with the surface of a first N-type heavily doped region and the surface of a first P-type heavily doped region of the other corresponding N-type well region of the electrostatic protection structure; And any one of the two connecting ends of the conductive connecting structure is connected with the surface of the second P-type heavily doped region and the surface of the second N-type heavily doped region of the corresponding electrostatic protection structure.
2. The ESD protection device of claim 1 further comprising an interlayer dielectric layer, a metal dielectric layer, and a passivation layer; The interlayer dielectric layer is positioned on the surface of the substrate; The intermetallic dielectric layer is positioned on the surface of the interlayer dielectric layer; the passivation layer is positioned on the surface of the intermetallic dielectric layer.
3. The ESD protection device of claim 2 wherein the anode, the cathode and the conductive connection structure each comprise a plurality of first conductive contact structures, a plurality of first conductive layers, a plurality of second conductive contact structures and a plurality of second conductive layers; Each first conductive contact structure penetrates through the interlayer dielectric layer; the surface of each first N-type heavily doped region and the surface of each first P-type heavily doped region of one electrostatic protection structure are respectively connected with the first conductive contact structure of one anode, the surface of each first N-type heavily doped region and the surface of each first P-type heavily doped region of the other electrostatic protection structure are respectively connected with the first conductive contact structure of one cathode, and the surface of each second P-type heavily doped region and the surface of each second N-type heavily doped region are respectively connected with the first conductive contact structure of one conductive connection structure; the first conductive layers are positioned on the surface of the interlayer dielectric layer, wherein the surfaces of the two first conductive contact structures on each N-type well region under the anode are provided with first conductive layers of one anode, the two first conductive contact structures on each N-type well region under the cathode are connected with first conductive layers of one cathode, and the two first conductive contact structures on each P-type well region are provided with first conductive layers of one conductive connection structure; Each second conductive contact structure is positioned in the intermetallic dielectric layer, and the surface of each second conductive contact structure is exposed by the intermetallic dielectric layer, wherein the surface of each first conductive layer is provided with a corresponding second conductive contact structure; Wherein the surface of each anode is provided with a corresponding anode second layer conductive layer, the two second layer conductive layers of the anode are connected with each other, the surface of each cathode is provided with a corresponding cathode second layer conductive layer, the two second layer conductive layers of the cathode are connected with each other, the surface of the second conductive contact structure of the conductive connection structure is provided with a second layer conductive layer, and the two second layer conductive layers of the conductive connection structure are connected with each other.
4. The ESD protection device of claim 3 further comprising a custom layer on top of the substrate.
5. The ESD protection device of claim 1 wherein the substrate is a P-type substrate.
6. A method of manufacturing an ESD protection device comprising: Providing a substrate; Two static protection structures are formed in the substrate, each static protection structure is internally provided with a P-type well region positioned in the substrate and two N-type well regions respectively positioned in the two sides of the P-type well region along a first direction, a first N-type heavily doped region and a first P-type heavily doped region which are adjacent along the first direction are arranged in the N-type well region, a second N-type heavily doped region and a second P-type heavily doped region which are distributed at intervals along the first direction are arranged in the P-type well region, a P-type shallow doped region is also arranged in one N-type well region in the 2N-type well regions, the P-type shallow doped region is positioned between the second N-type heavily doped region and the first P-type heavily doped region in one N-type well region, the P-type shallow doped region and the first P-type heavily doped region in the N-type well region are distributed at intervals along the first direction, the P-type heavily doped region extends to at least to the junction of the P-type well region and the one N-type well region, and the P-type heavily doped region extends to the surface of the first N-type well region along the first direction; Forming an anode, wherein either one of the two connection ends of the anode is connected with the surface of a first N-type heavily doped region and the surface of a first P-type heavily doped region of an N-type well region of a corresponding electrostatic protection structure, and Forming a cathode, wherein any one of two connecting ends of the cathode is connected with the surface of a first N-type heavily doped region and the surface of a first P-type heavily doped region of a corresponding N-type well region of the other electrostatic protection structure; And forming a conductive connection structure, wherein any one of two connection ends of the conductive connection structure is connected with the surface of a second P-type heavily doped region and the surface of a second N-type heavily doped region of a corresponding electrostatic protection structure.
7. The method of manufacturing an ESD protection device of claim 6, further comprising: Forming an interlayer dielectric layer on the surface of the substrate after forming the electrostatic protection structure; Forming an intermetallic dielectric layer on the surface of the interlayer dielectric layer; And forming a passivation layer on the surface of the intermetallic dielectric layer.
8. The method of manufacturing an ESD protection device of claim 7 wherein after forming the interlayer dielectric layer and before forming the inter-metal dielectric layer, a plurality of first conductive contact structures penetrating the interlayer dielectric layer are formed, wherein the surface of each of the first N-type heavily doped regions and the surface of each of the first P-type heavily doped regions of one of the electrostatic protection structures are respectively connected with the first conductive contact structures of one of the anodes; the surface of each first N-type heavily doped region and the surface of each first P-type heavily doped region of the other electrostatic protection structure of the two electrostatic protection structures are respectively connected with a first conductive contact structure of the cathode; the surface of each second P-type heavily doped region and the surface of each second N-type heavily doped region are respectively connected with a first conductive contact structure of the conductive connection structure; After the first conductive contact structures are formed and before the inter-metal dielectric layers are formed, forming a plurality of first conductive layers on the surfaces of the inter-layer dielectric layers, wherein the surfaces of the two first conductive contact structures on each N-type well region under the anode are provided with first conductive layers of one anode, the two first conductive contact structures on each N-type well region under the cathode are connected with first conductive layers of one cathode, and the two first conductive contact structures on each P-type well region are provided with first conductive layers of one conductive connection structure; Forming a plurality of second conductive contact structures in the intermetallic dielectric layer after the intermetallic dielectric layer is formed and before the passivation layer is formed, wherein each second conductive contact structure is exposed by the surface of the intermetallic dielectric layer; Forming a second conductive layer on the surface of the intermetallic dielectric layer after the second conductive contact structure is formed and before the passivation layer is formed, wherein the surface of the second conductive contact structure of each anode is provided with a corresponding anode second conductive layer, the two second conductive layers of the anode are connected with each other, the surface of the second conductive contact structure of each cathode is provided with a corresponding cathode second conductive layer, the two second conductive layers of the cathode are connected with each other, the surface of the second conductive contact structure of the conductive connection structure is provided with a second conductive layer, and the two second conductive layers of the conductive connection structure are connected with each other; And after forming the passivation layer on the surface of the intermetallic dielectric layer and the surface of the second conductive layer, etching the passivation layer until the surface of the second conductive layer is exposed.
9. The method of manufacturing an ESD protection device of claim 8 wherein P-type ions are implanted into the substrate to form a patterned layer on the surface of the substrate prior to forming the interlayer dielectric layer.
10. The method of manufacturing an ESD protection device of claim 6 wherein P-type ions are doped in the substrate prior to forming the electrostatic protection structure.

Description

ESD protection device and method for manufacturing the same Technical Field The invention relates to the technical field of semiconductors, in particular to an ESD protection device and a preparation method thereof. Background An electrostatic discharge (Electronic STATIC DISCHARGE, ESD) protection device is an indispensable part for ensuring the normal operation of a chip, especially in a CMOS integrated circuit, the continuous progress of the process makes the gate oxide layer of the device thinner and thinner, and the breakdown voltage of the device is lower and lower, which puts higher demands on the performance of the ESD protection device. The silicon controlled rectifier (Silicon Controlled Rectifier, SCR) has the advantage of low clamp voltage and large on-current as an ESD protection device. However, SCR has a large parasitic capacitance as an ESD protection device, and excessive parasitic capacitance of the ESD protection device affects the performance of the ESD protection device. Disclosure of Invention The invention provides an ESD protection device and a preparation method thereof, which reduce parasitic capacitance of the ESD protection device and have lower clamping voltage and larger on-current. According to a first aspect of the present invention, an ESD protection device is provided, comprising: A substrate; The two electrostatic protection structures are positioned in the substrate, each electrostatic protection structure comprises a P-type well region positioned in the substrate, two N-type well regions respectively positioned in the two sides of the P-type well region along a first direction, a first N-type heavily doped region and a first P-type heavily doped region which are adjacent along the first direction are arranged in the N-type well region, a second N-type heavily doped region and a second P-type heavily doped region which are distributed at intervals along the first direction are arranged in the P-type well region, a P-type shallow doped region is also arranged in one N-type well region in the 2N-type well regions, the P-type shallow doped region is positioned between the second N-type heavily doped region and the first P-type heavily doped region in one N-type well region, the P-type shallow doped region and the first P-type heavily doped region in one N-type well region are distributed at intervals and extend to at least to the junction of the P-type region and the first N-type heavily doped region, and the P-type well region extends to the surface of the other N-type well region along the first direction; The electrostatic protection structure comprises an anode and a cathode, wherein any one of two connecting ends of the anode is connected with the surface of a first N-type heavily doped region and the surface of a first P-type heavily doped region of one corresponding N-type well region of the electrostatic protection structure, and any one of two connecting ends of the cathode is connected with the surface of a first N-type heavily doped region and the surface of a first P-type heavily doped region of the other corresponding N-type well region of the electrostatic protection structure; And any one of the two connecting ends of the conductive connecting structure is connected with the surface of the second P-type heavily doped region and the surface of the second N-type heavily doped region of the corresponding electrostatic protection structure. Optionally, the semiconductor device further comprises an interlayer dielectric layer, a metal dielectric layer and a passivation layer; The interlayer dielectric layer is positioned on the surface of the substrate; The intermetallic dielectric layer is positioned on the surface of the interlayer dielectric layer; the passivation layer is positioned on the surface of the intermetallic dielectric layer. Optionally, the anode, the cathode and the conductive connection structure comprise a plurality of first conductive contact structures, a plurality of first conductive layers, a plurality of second conductive contact structures and a plurality of second conductive layers; Each first conductive contact structure penetrates through the interlayer dielectric layer; the surface of each first N-type heavily doped region and the surface of each first P-type heavily doped region of one electrostatic protection structure are respectively connected with the first conductive contact structure of one anode, the surface of each first N-type heavily doped region and the surface of each first P-type heavily doped region of the other electrostatic protection structure are respectively connected with the first conductive contact structure of one cathode, and the surface of each second P-type heavily doped region and the surface of each second N-type heavily doped region are respectively connected with the first conductive contact structure of one conductive connection structure; the first conductive layers are positioned on the surface of the in