US-20260129976-A1 - ELECTROSTATIC DISCHARGE PROTECTION DEVICE

US20260129976A1US 20260129976 A1US20260129976 A1US 20260129976A1US-20260129976-A1

Abstract

An electrostatic discharge protection device includes a diode, a voltage clamping component, an electronic component, a first pin, and a second pin. The diode includes a first doped area of a first conductivity type and a second doped area of a second conductivity type opposite to the first conductivity type. The voltage clamping component is electrically connected to the first doped area. The electronic component includes a first region of the first conductivity type, a second region of the second conductivity type, a third region of the first conductivity type, and a fourth region of the second conductivity type. The first region is electrically connected to the second doped area. The second region is electrically connected to the first doped area and the voltage clamping component. The fourth region is electrically connected to the voltage clamping component.

Inventors

Chih-Wei Chen
Kuan-Yu Lin
Kun-Hsien Lin

Assignees

AMAZING MICROELECTRONIC CORP.

Dates

Publication Date: 20260507
Application Date: 20241106

Claims (14)

1 . An electrostatic discharge protection device comprising: at least one voltage clamping device comprising: a diode comprising a first doped area of a first conductivity type and a second doped area of a second conductivity type opposite to the first conductivity type; a voltage clamping component having a first terminal and a second terminal, wherein the first terminal of the voltage clamping component is electrically connected to the first doped area; an electronic component comprising a first region of the first conductivity type, a second region of the second conductivity type, a third region of the first conductivity type, and a fourth region of the second conductivity type, wherein the first region, the second region, the third region, and the fourth region are adjacent to each other, the second region is arranged between the first region and the third region, the third region is arranged between the second region and the fourth region, the first region is electrically connected to the second doped area, the second region is electrically connected to the first doped area and the first terminal of the voltage clamping component, the fourth region is electrically connected to the second terminal of the voltage clamping component; a first pin electrically connected to the second doped area and the first region; and a second pin electrically connected to the second terminal of the voltage clamping component and the fourth region.
2 . The electrostatic discharge protection device according to claim 1 , wherein the first conductivity type is an N type and the second conductivity type is a P type.
3 . The electrostatic discharge protection device according to claim 2 , wherein when the first pin receives a positive pulse voltage and the second pin receives a reference voltage lower than the positive pulse voltage, an electrostatic discharge current flows from the first pin to the second pin through the diode and the voltage clamping component, and when the first pin receives a negative pulse voltage and the second pin receives a reference voltage higher than the negative pulse voltage, a first electrostatic discharge current flows from the second pin to the first pin through the voltage clamping component, the second region, and the first region and a second electrostatic discharge current flows from the second pin to the first pin through the electronic component.
4 . The electrostatic discharge protection device according to claim 1 , wherein the first conductivity type is a P type and the second conductivity type is an N type.
5 . The electrostatic discharge protection device according to claim 4 , wherein when the second pin receives a reference voltage and the first pin receives a negative pulse voltage lower than the reference voltage, an electrostatic discharge current flows from the second pin to the first pin through the voltage clamping component and the diode, and when the first pin receives a positive pulse voltage and the second pin receives a reference voltage lower than the positive pulse voltage, a first electrostatic discharge current flows from the first pin to the second pin through the first region, the second region, and the voltage clamping component and a second electrostatic discharge current flows from the first pin to the second pin through the electronic component.
6 . The electrostatic discharge protection device according to claim 1 , wherein the voltage clamping component is a Zener diode, an NPN bipolar junction transistor whose base is electrically floating, an NPN bipolar junction transistor whose emitter is coupled to its base, a PNP bipolar junction transistor whose base is electrically floating, or a PNP bipolar junction transistor whose emitter is coupled to its base.
7 . The electrostatic discharge protection device according to claim 1 , wherein the at least one voltage clamping device comprises two voltage clamping devices, and the second pin of one of the two voltage clamping devices is electrically connected to the second pin of another of the two voltage clamping devices.
8 . The electrostatic discharge protection device according to claim 1 , wherein the at least one voltage clamping device comprises two voltage clamping devices, and the first pin of one of the two voltage clamping devices is electrically connected to the first pin of another of the two voltage clamping devices.
9 . The electrostatic discharge protection device according to claim 1 , wherein the fourth region is implemented with a heavily-doped region, the third region is implemented with a first epitaxial region and a second epitaxial region, the second region is implemented with a first doped well, the first region is implemented with a first heavily-doped area, the first epitaxial region and the second epitaxial region are sequentially formed on the heavily-doped region, the first doped well is formed in the second epitaxial region, the first heavily-doped area and a second heavily-doped area of the second conductivity type are formed in the first doped well, a third heavily-doped area of the first conductivity type and a fourth heavily-doped area of the second conductivity type are formed in the second epitaxial region, the second heavily-doped area is electrically connected to the third heavily-doped area, the first heavily-doped area is electrically connected to the fourth heavily-doped area, the first doped area is implemented with the second epitaxial region and the third heavily-doped area, the second doped area is implemented with the fourth heavily-doped area, the voltage clamping component is implemented with the heavily-doped region and the first epitaxial region.
10 . The electrostatic discharge protection device according to claim 9 , wherein a doping concentration of the first epitaxial region is greater than or equal to that of the second epitaxial region.
11 . The electrostatic discharge protection device according to claim 9 , further comprising two isolation structures formed in the heavily-doped region, the first epitaxial region, and the second epitaxial region, one of the isolation structures surrounds the first doped well, the first heavily-doped area, and the second heavily-doped area, and another of the isolation structures surrounds the third heavily-doped area and the fourth heavily-doped area.
12 . The electrostatic discharge protection device according to claim 9 , further comprising a buried region of the first conductivity type formed in the first epitaxial region and formed between the fourth heavily-doped area and the heavily-doped region, wherein a doping concentration of the buried region is greater than that of the first epitaxial region.
13 . The electrostatic discharge protection device according to claim 1 , wherein the fourth region is implemented with a heavily-doped region, the third region is implemented with a first epitaxial region and a second epitaxial region, the second region is implemented with a first doped well, the first region is implemented with a first heavily-doped area, the first epitaxial region and the second epitaxial region are sequentially formed on the heavily-doped region, the first doped well and a second doped well of the first conductivity type are formed in the second epitaxial region, the first heavily-doped area and a second heavily-doped area of the second conductivity type are formed in the first doped well, a third heavily-doped area of the first conductivity type and a fourth heavily-doped area of the second conductivity type are formed in the second doped well, the second heavily-doped area is electrically connected to the third heavily-doped area, the first heavily-doped area is electrically connected to the fourth heavily-doped area, the first doped area is implemented with the second doped well and the third heavily-doped area, the second doped area is implemented with the fourth heavily-doped area, the voltage clamping component is implemented with the heavily-doped region and the first epitaxial region.
14 . The electrostatic discharge protection device according to claim 1 , wherein the fourth region is implemented with a heavily-doped region, the third region is implemented with a first epitaxial region, the second region is implemented with a second epitaxial region, the first region is implemented with a first heavily-doped area, the first epitaxial region and the second epitaxial region are sequentially formed on the heavily-doped region, the first heavily-doped area and a second heavily-doped area of the second conductivity type are formed in the second epitaxial region, a third heavily-doped area of the first conductivity type and a fourth heavily-doped area of the second conductivity type are formed in a doped well of the first conductivity type, the doped well is formed in the second epitaxial region, the second heavily-doped area is electrically connected to the third heavily-doped area, the first heavily-doped area is electrically connected to the fourth heavily-doped area, the first doped area is implemented with the doped well and the third heavily-doped area, the second doped area is implemented with the fourth heavily-doped area, the voltage clamping component is implemented with the heavily-doped region and the first epitaxial region.

Description

BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The present invention relates to a protection device, particularly to an electrostatic discharge protection device. DESCRIPTION OF THE RELATED ART As the IC device sizes have been shrunk to nanometer scale, the consumer electronics, like the laptop and mobile devices, have been designed to be much smaller than ever. Without suitable protection devices, the functions of these electronics could be reset or even damaged under electrostatic discharge (ESD) events. Currently, all consumer electronics are expected to pass the ESD test requirement of IEC 61000-4-2 standard. Transient voltage suppressor (TVS) is generally designed to bypass the ESD energy, so that the electronic systems can be prevented from ESD damages. The working principle of transient voltage suppression (TVS) device is shown in FIG. 1. In FIG. 1, a TVS device 10 is connected in parallel with a protected circuit 12 on the printed circuit board (PCB). The transient voltage suppression device 10 would be triggered immediately when the ESD event occurs. In that way, the transient voltage suppression device 10 can provide a superiorly low resistance path for discharging the transient ESD current, so that the energy of the ESD transient current can be bypassed by the transient voltage suppression device 10. The US Patent No. 8217421 B2 disclosed a uni-directional vertical PNP electrostatic discharge device triggered by a trigger node. The parasitic capacitance of the vertical PNP electrostatic discharge device depends on a P-type heavily-doped area, an N-type well, a P-type heavily-doped substrate, and a P-type well. Thus, the vertical PNP electrostatic discharge device has a large parasitic capacitance. The US Patent Publication No.2018/0047717 A1 disclosed a vertical NPN bipolar junction transistor connected to a diode in parallel. Since the diode is a single-junction capacitance component, the overall capacitance of the ESD protection device is large. The US Patent No. 10930637 B2 disclosed a vertical bipolar junction transistor connected to a PNPN diode in parallel. The PNPN diode has a reverse-biased junction to cause a higher trigger voltage when the PNPN diode is turned on. To overcome the abovementioned problems, the present invention provides an electrostatic discharge protection device, so as to solve the afore-mentioned problems of the prior art. SUMMARY OF THE INVENTION The present invention provides an electrostatic discharge protection device, which has low capacitance and low trigger voltage. In an embodiment of the present invention, an electrostatic discharge protection device includes at least one voltage clamping device. The voltage clamping device includes a diode, a voltage clamping component, an electronic component, a first pin, and a second pin. The diode includes a first doped area of a first conductivity type and a second doped area of a second conductivity type opposite to the first conductivity type. The voltage clamping component has a first terminal and a second terminal. The first terminal of the voltage clamping component is electrically connected to the first doped area. The electronic component includes a first region of the first conductivity type, a second region of the second conductivity type, a third region of the first conductivity type, and a fourth region of the second conductivity type. The first region, the second region, the third region, and the fourth region are adjacent to each other. The second region is arranged between the first region and the third region. The third region is arranged between the second region and the fourth region. The first region is electrically connected to the second doped area. The second region is electrically connected to the first doped area and the first terminal of the voltage clamping component. The fourth region is electrically connected to the second terminal of the voltage clamping component. The first pin is electrically connected to the second doped area and the first region. The second pin is electrically connected to the second terminal of the voltage clamping component and the fourth region. In an embodiment of the present invention, the first conductivity type is an N type and the second conductivity type is a P type. In an embodiment of the present invention, when the first pin receives a positive pulse voltage and the second pin receives a reference voltage lower than the positive pulse voltage, an electrostatic discharge current flows from the first pin to the second pin through the diode and the voltage clamping component. And when the first pin receives a negative pulse voltage and the second pin receives a reference voltage higher than the negative pulse voltage, a first electrostatic discharge current flows from the second pin to the first pin through the voltage clamping component, the second region, and the first region and a second electrostatic discharge current flows from the second pin to the first