CN-122028508-A - Bidirectional low-capacity longitudinal structure SCR (selective catalytic reduction) characteristic transient voltage suppression device

CN122028508ACN 122028508 ACN122028508 ACN 122028508ACN-122028508-A

Abstract

The embodiment of the application provides a bidirectional low-capacity longitudinal structure SCR (selective catalytic reduction) characteristic transient voltage suppression device, which comprises a first SCR structure from the front surface to the back surface of the device and a second SCR structure from the back surface to the front surface, wherein a first groove, a second groove and a third groove are arranged between the first SCR structure and the second SCR structure to form the bidirectional low-capacity longitudinal structure SCR characteristic transient voltage suppression device.

Inventors

LI DENGHUI
XU CHENGZONG
Liu Lanshen

Assignees

豪威集成电路(集团)股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260210

Claims (6)

1. A bidirectional low-capacitance longitudinal structure SCR characteristic transient voltage suppression device is characterized by comprising a first SCR structure from the front surface to the back surface of the device and a second SCR structure from the back surface to the front surface; The first SCR structure and the second SCR structure comprise a first epitaxial layer and a second epitaxial layer, and the first epitaxial layer and the second epitaxial layer are sequentially arranged above the substrate from bottom to top; A first groove, a second groove and a third groove are arranged between the first SCR structure and the second SCR structure, the first groove is close to the first SCR structure, and the third groove is close to the second SCR structure; The first groove, the second groove and the third groove are arranged at intervals, and the first groove and the second groove penetrate through the second epitaxial layer and the first epitaxial layer and extend into the substrate; One end of the first SCR structure and one end of the second SCR structure are connected with the first input/output interface, the other end of the first SCR structure and the other end of the second SCR structure are connected with the second input/output interface, and the two-way low-capacity longitudinal structure SCR characteristic transient voltage suppression device is formed by the first SCR structure and the second SCR structure in an anti-parallel mode.
2. A bi-directional low capacitance vertical structure SCR specific transient voltage suppression device as defined in claim 1 comprising: A fourth groove is formed in one side, far away from the first groove, of the first SCR structure, and penetrates through the second epitaxial layer and the first epitaxial layer and extends into the substrate; A fifth groove, a sixth groove and a seventh groove are arranged at one side of the second SCR structure far away from the first groove, and are mutually arranged at intervals, and the sixth groove and the seventh groove penetrate through the second epitaxial layer and the first epitaxial layer and extend into the substrate; the fifth groove is arranged close to the second SCR structure; the fifth groove and the seventh groove are filled with insulating materials, and the sixth groove is filled with conductive materials.
3. The SCR specific transient voltage suppression device of bi-directional low capacitance vertical structure as recited in claim 1 or 2, wherein the first SCR structure comprises a P-type first injection region, an N-type second epitaxial layer, an N-type second injection region, a P-type first epitaxial layer, and an N-type substrate disposed between the first input output interface and the second input output interface; the second SCR structure comprises a P-type first epitaxial layer, an N-type second epitaxial layer, a P-type well region and an N-type third injection region which are arranged between the second input/output interface and the first input/output interface; The first injection region and the well region are arranged in the second epitaxial layer, and the third injection region is arranged in the well region; the second implant region is disposed in the first epitaxial layer.
4. A bi-directional low capacity vertical structure SCR characteristic transient voltage suppression device as recited in claim 3, wherein said second trench and sixth trench are plural.
5. The device for suppressing transient voltage of SCR characteristic of bi-directional low-capacitance vertical structure according to claim 3, wherein N-type fourth injection region and N-type fifth injection region are symmetrically arranged at both sides of said well region; The fourth injection region is arranged between the third groove and the well region; the fifth implant region is disposed between the fifth trench and the well region.
6. A bi-directional low capacitance vertical structure SCR specific transient voltage suppression device as defined in claim 3 wherein said insulating material is silicon dioxide and said conductive material is tungsten metal.

Description

Bidirectional low-capacity longitudinal structure SCR (selective catalytic reduction) characteristic transient voltage suppression device Technical Field The embodiment of the application relates to the technical field of semiconductors, in particular to a bidirectional low-capacity longitudinal structure SCR characteristic transient voltage suppression device. Background With the increasing signal transmission rate of electronic products, the process of the back-end IC device is more advanced, and the weaker the electronic products have to withstand ESD (electrostatic discharge) and EOS (electrical overstress), which requires the addition of a transient voltage suppression protection device (TVS) to protect the back-end IC of the electronic products, and simultaneously requires a higher requirement on the TVS device, and requires a lower clamping voltage and a smaller capacitance. However, the existing bidirectional SCR products are all of a transverse structure (current flows transversely) due to process limitation, but the effective area of the transverse structure SCR products is only available on the side edges in the working process, so that the maximum antistatic capacity is weak. Meanwhile, due to the transverse structure, the positive electrode and the negative electrode can only be led out from the same surface, so that the packaging is greatly limited. Disclosure of Invention In order to solve or alleviate the problems in the prior art, the embodiment of the application provides a bidirectional low-capacitance vertical structure SCR characteristic transient voltage suppression device, which comprises a first SCR structure from the front surface to the back surface of the device and a second SCR structure from the back surface to the front surface; The first SCR structure and the second SCR structure comprise a first epitaxial layer and a second epitaxial layer, and the first epitaxial layer and the second epitaxial layer are sequentially arranged above the substrate from bottom to top; A first groove, a second groove and a third groove are arranged between the first SCR structure and the second SCR structure, the first groove is close to the first SCR structure, and the third groove is close to the second SCR structure; The first groove, the second groove and the third groove are arranged at intervals, and the first groove and the second groove penetrate through the second epitaxial layer and the first epitaxial layer and extend into the substrate; One end of the first SCR structure and one end of the second SCR structure are connected with the first input/output interface, and the other ends of the first SCR structure and the second SCR structure are connected with the second input/output interface. As a preferred embodiment of the present application, it comprises: A fourth groove is formed in one side, far away from the first groove, of the first SCR structure, and penetrates through the second epitaxial layer and the first epitaxial layer and extends into the substrate; A fifth groove, a sixth groove and a seventh groove are arranged at one side of the second SCR structure far away from the first groove, and are mutually arranged at intervals, and the sixth groove and the seventh groove penetrate through the second epitaxial layer and the first epitaxial layer and extend into the substrate; the fifth groove is arranged close to the second SCR structure; the fifth groove and the seventh groove are filled with insulating materials, and the sixth groove is filled with conductive materials. As a preferred embodiment of the present application, the first SCR structure includes a P-type first injection region, an N-type second epitaxial layer, an N-type second injection region, a P-type first epitaxial layer, and an N-type substrate, which are disposed between the first input output interface and the second input output interface; the second SCR structure comprises a P-type first epitaxial layer, an N-type second epitaxial layer, a P-type well region and an N-type third injection region which are arranged between the second input/output interface and the first input/output interface; The first injection region and the well region are arranged in the second epitaxial layer, and the third injection region is arranged in the well region; the second implant region is disposed in the first epitaxial layer. As a preferred embodiment of the present application, the second grooves and the sixth grooves are plural. As a preferred embodiment of the application, the two sides of the well region are symmetrically provided with an N-type fourth injection region and an N-type fifth injection region; The fourth injection region is arranged between the third groove and the well region; the fifth implant region is disposed between the fifth trench and the well region. As a preferred embodiment of the present application, the insulating material is silicon dioxide, and the conductive material is tungsten metal. Comp