KR100336521B1 - corner gate type thyristor device - Google Patents

Abstract

A corner gate type thyristor device is disclosed that can minimize reactive current components and improve trigger characteristics during on-state switching of the device.

In order to accomplish this, the present invention provides a semiconductor device comprising: a P-type gate region formed in a predetermined portion toward a first surface in an N-type semiconductor substrate; A P-type anode region formed on the second surface side in the substrate; A P + type device isolation region formed through the substrate and the anode region; An N + type cathode region formed at a predetermined surface side in the gate region to have a predetermined junction depth, and having a plurality of gate region islands along an edge portion thereof; A cathode electrode formed on the cathode region; A corner gate electrode formed on the gate region; A gate line disposed along an edge of the cathode region to be integrally connected with the corner gate electrode, the gate line including a plurality of dummy gate electrodes connected to the gate region island; And a corner gate type thyristor element formed of an anode electrode formed on the anode region.

Description

Corner gate type thyristor device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device, and more particularly to a corner gate type thyristor device capable of minimizing reactive current components to improve trigger characteristics.

The thyristor element has a unidirectional trigger characteristic of the NPNP structure, and is mainly used in an AC switching power supply circuit in which the anode voltage is periodically changed. The device is largely composed of three terminals, a gate G, an anode A, and a cathode K. In general, a bias voltage is applied to the anode and a signal current is applied to the gate while the cathode is grounded. It is possible to switch the device on-state.

1A and 1B show a conventional corner gate type NPNP thyristor element structure having the above operating characteristics. Here, FIG. 1A shows a plan view from above of the device and FIG. 1B shows a vertical cross-sectional view showing the X-X cross section structure of FIG. 1A.

1A and 1B, a conventional corner gate type thyristor element has a P-type gate region 6 and an anode toward the first and second surfaces 2 and 3 in the N-type semiconductor substrate 1, respectively. A region 5 is formed, an N + type cathode region 7 is formed on the surface side of the gate region 6, and a P + type isolation is formed through the substrate 1 and the anode region 5. A region 4 is formed, and a corner gate electrode 9 and a cathode electrode 10 connected one-to-one with the gate region 6 and the cathode region 7 are formed on the first surface 2 on the substrate 1. It can be seen that the second surface 3 on the substrate 1 has a structure in which an anode electrode 8 connected to the anode region 5 is formed. Herein, reference numeral 11 denotes an insulating film, and a dotted line in the gate electrode 9 represents a real contact surface between the gate electrode 9 and the gate region 6.

At this time, the cathode region 7 is designed to be adjacent to only a part of the outer surface of the gate electrode 9 as shown in the plan view of FIG. 1A due to the relationship of the gate electrode 9 located at the corner.

Therefore, in the thyristor element of the above structure, the gate current applied to turn the element on-state is distributed in the direction of the arrow shown in Fig. 1A.

Therefore, when the corner gate type thyristor element is designed to have the above structure, the signal current applied to the gate electrode for the on-state switching of the element does not contribute to the driving of the element, and a part thereof (part denoted by reference A) Only the current) contributes.

This is because of the structural characteristic that only a part of the corner gate electrode is designed to be adjacent to the cathode region, which is the portion of the A portion adjacent to the cathode region 7 of the signal current applied to the gate electrode 9 and distributed along its periphery. This is because only the current is effectively used, and the current in the portion (other than A) is not directly involved in driving the element and is lost as it is. This loss current is called reactive current.

Therefore, under the above structure, in consideration of the current lost in the portion other than the region A, the signal current increased by this loss amount must be supplied to the corner gate electrode so that the device can be switched on-state, so that the trigger current increases when the device is driven. Problem occurs.

Accordingly, an object of the present invention is to change the structure of the thyristor element so that the signal current applied to the corner gate electrode effectively contributes to the entire area of the cathode, thereby minimizing the reactive current component and switching the on-state state of the element. The present invention provides a corner gate type thyristor device for improving the characteristics.

1A and 1B show a conventional corner gate type NPNP thyristor device structure,

1a is a plan view thereof;

Figure 1b is a vertical cross-sectional view showing the X-X cross section structure of Figure 1a,

2A and 2B illustrate a corner gate type NPNP thyristor device structure according to the present invention.

2a is a plan view thereof;

Figure 2b is a vertical cross-sectional view showing the X-X cross section structure of Figure 2a.

In order to achieve the above object, according to the present invention, there is provided a semiconductor device comprising: a P-type gate region formed in a predetermined portion toward a first surface in an N-type semiconductor substrate; A P-type anode region formed on the second surface side in the substrate; A P + type device isolation region formed through the substrate and the anode region; An N + type cathode region formed at a predetermined surface side in the gate region to have a predetermined junction depth, and having a plurality of gate region islands along an edge portion thereof; A cathode electrode formed on the cathode region; A corner gate electrode formed on the gate region; A gate line disposed along an edge of the cathode region to be integrally connected with the corner gate electrode, the gate line including a plurality of dummy gate electrodes connected to the gate region island; And a corner gate type thyristor element formed of an anode electrode formed on the anode region.

When the thyristor element is designed to have the above structure, a plurality of dummy gate electrodes are formed along the edge of the cathode region (where the gate region island is formed) in addition to the portion where the corner gate electrode is to be formed. When the signal current is applied to the gate electrode, all of the dummy gate electrodes are subjected to the same signal current, thereby minimizing the reactive current component during the on-state switching of the device.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

2A and 2B show a corner gate type NPNP thyristor device structure proposed in the present invention, FIG. 2A shows a top view of the device from above and FIG. 2B shows a vertical sectional view showing the XX cross section structure of FIG. 2A. Indicates.

2A and 2B, the corner gate type thyristor element proposed in the present invention has a P type gate region 6 toward the first and second surfaces 2 and 3 in the N type semiconductor substrate 1. And an anode region 5 are formed, and a P + type isolation region 4 is formed through the substrate 1 and the anode region 5, and along the edge portion of the gate region 6 along the surface side. N + type cathode regions 7a and 7b having a plurality of gate region islands 6a are formed, and a cathode electrode 10 is connected on the cathode region 7a, and the cathode region 7a is disposed on one side of the cathode region 7a. Corner gate electrodes 9 are connected on the gate region 6, and a plurality of dummy gate electrodes 9a, 9b connected to the gate region islands 6a along edges of the cathode region 7b, A gate line 9 'provided with 9c is formed, and an anode is formed on the anode region 5. Pole is 8 shows that consists of a structure in which the connection. Herein, reference numeral 11 denotes an insulating film, and a dotted line in the corner gate electrode 9 represents a real contact surface between the gate electrode and the gate region 6, and in the dummy gate electrodes 9a, 9b, and 9c. The dotted line represents the real contact surface between the gate electrode and the gate region island 6a.

In this case, the gate region island 6a is formed to be disposed at each corner of the cathode region 7b, and the gate line 9 'and the corner gate electrode 9 are connected to the corner gate electrode 9 with a signal current. In order to apply the same signal current to the dummy gate electrodes 9a, 9b, and 9c during application, the dummy gate electrodes 9a, 9b, and 9c are integrally connected along the edge of the cathode region 7b.

In this way, the gate lines 9 'provided with dummy gate electrodes 9a, 9b, and 9c are additionally formed along the edges of the cathode region 7b. This is to allow the signal current applied to to effectively contribute to the entire area of the cathode.

Therefore, the thyristor element of the above structure is manufactured through the following third step process.

As a first step, a P + type source (e.g., B) is respectively deposited on predetermined portions on the first and second surfaces 2 and 3 of the N-type semiconductor substrate 1, and then hot-diffused. A P + type device isolation region 4 is formed in the device isolation region in the substrate 1.

As a second step, the P-type source is deposited on the first and second surfaces 2 and 3 of the substrate 1, respectively, and then diffused so that the first surface 2 in the substrate 1 is A gate region 6 is formed, and an anode region 5 is formed on the side of the second surface 3 in the substrate 1. Subsequently, an N + -type source is selectively precipitated on the surface side in the gate region 6 and then diffused to form a cathode region 7a having a plurality of gate region islands 6a along edges (especially, corners). , 7b).

As a third step, a gate is provided with corner gate electrodes 9 and dummy gate electrodes 9a, 9b, 9c on the first surface side of the substrate 1 through metal film deposition and etching thereof. The process of this process is completed by forming the line 9 'and the cathode electrode 10, and forming the anode electrode 8 connected to the anode region 5 on the second surface side of the substrate 1. At this time, the corner gate electrode 9 is formed to be connected to the gate region 6 on one side of the cathode region 7a as mentioned above, and the gate line 9 'is integrally formed with the corner gate electrode 9. It is formed to be disposed along the edge of the cathode region 7b so as to be connected, and the cathode electrode 10 is formed to be connected to the cathode region 7a.

When the thyristor element is designed to have the structures shown in Figs. 2A and 2B based on the above process procedure, the edge portion of the cathode region 7b (the gate region island 6a) is formed in addition to the portion where the corner gate electrode is to be formed. Since the dummy gate electrodes 9a, 9b, and 9c are formed along the portion thereof, these dummy gate electrodes 9a, 9b, and 9c are applied when the signal current is applied to the corner gate electrode 9, respectively. ), The same signal current is applied to all of them. As a result, when the device is to be turned on, the signal current contributes to the cathode area more efficiently than before, thereby minimizing the reactive current component when driving the device, and also reducing the trigger current. You can do it.

As described above, according to the present invention, by changing the structure of the cathode region and the gate electrode so that the signal current applied to the gate electrode can effectively contribute to the entire area of the cathode, the reactive current during the on-state switching of the device Minimizing the components allows for improved trigger characteristics.

Claims (2)

A P-type gate region formed in a predetermined portion toward the first surface in the N-type semiconductor substrate; A P-type anode region formed on the second surface side in the substrate; A P + type device isolation region formed through the substrate and the anode region; An N + type cathode region formed at a predetermined surface side in the gate region to have a predetermined junction depth, and having a plurality of gate region islands along an edge portion thereof; A cathode electrode formed on the cathode region; A corner gate electrode formed on the gate region; A gate line disposed along an edge of the cathode region to be integrally connected with the corner gate electrode, the gate line including a plurality of dummy gate electrodes connected to the gate region island; And A corner gate type thyristor element, characterized in that consisting of an anode electrode formed on the anode region. The corner gate type thyristor element according to claim 1, wherein the gate region islands are formed at each corner of the cathode region.