CN211455691U

CN211455691U - IGBT device structure capable of improving opening controllability

Info

Publication number: CN211455691U
Application number: CN202020383033.XU
Authority: CN
Inventors: 马克强; 金涛; 秦潇峰; 蒋兴莉; 王思亮
Original assignee: Semi Future Technology Co
Current assignee: Semi Future Technology Co
Priority date: 2020-03-24
Filing date: 2020-03-24
Publication date: 2020-09-08
Anticipated expiration: 2030-03-24

Abstract

The application relates to the field of semiconductor manufacturing, in particular to an IGBT device structure capable of effectively solving the problem that the traditional IGBT device structure is poor in opening controllability and capable of improving the opening controllability, the IGBT device structure comprises an N-type base region, a groove-type gate region is arranged in the N-type base region, the groove-type gate region comprises a gate oxide layer, a polycrystalline gate and a gate electrode, the polycrystalline gate is located inside the gate oxide layer, and the gate electrode is located on the upper surface of the polycrystalline gate and connected with the polycrystalline gate; p-type heavily doped regions are arranged on the left upper portion and the right upper portion of the N-type base region, an N-type heavily doped region is arranged on the surface layer in the N-type base region, and the portions, located in the P-type heavily doped regions, of the N-type heavily doped regions are separated by an etching process. The P-type deep doping area is not connected with the groove-shaped gate area, an inversion channel connecting the P-type base area and the P-type deep doping area is not easily formed below the groove in the gate pressurization opening process, the floating potential of the P-type deep doping area is reduced in the change rate in the opening process, therefore, the influence on the gate area is reduced, and the stability of gate voltage is improved.

Description

IGBT device structure capable of improving opening controllability

Technical Field

The application relates to the field of semiconductor manufacturing, in particular to an IGBT device structure capable of effectively improving opening controllability of traditional IGBT with poor opening controllability.

Background

In the field of power semiconductors, Insulated Gate Bipolar Transistors (IGBTs) often adopt a trench gate structure, and the purpose of controlling the on and off of a device is achieved by controlling the voltage of a gate. In the prior art, in order to reduce the conduction voltage drop of the device, a carrier injection enhancement technology is mostly adopted, namely, a floating area of the device is increased, as shown in fig. 1. The introduction of the floating zone reduces the conduction voltage drop Vcesat, but also reduces the opening controllability of the grid electrode to the device. The specific expression is that a large current change rate (di/dt) is generated in the turn-on process, and the value of the di/dt is changed little along with the change of the size of the grid drive resistance. The current change rate is coupled with the parasitic inductance of the peripheral circuit, an uncontrolled voltage is generated, and the whole circuit system is unstable in operation and vibrates. In addition, the existence of the floating space area causes the problem that the potential of the floating space area reversely charges the grid electrode in the starting process, so that the grid electrode is easy to vibrate.

Disclosure of Invention

In order to overcome the above problems of the existing IGBT, an IGBT device structure with improved turn-on controllability is proposed.

In order to achieve the technical effects, the technical scheme of the application is as follows:

the utility model provides an improve IGBT device structure of opening controllability which characterized in that: the N-type base region is internally provided with a groove-type gate region, the groove-type gate region comprises a gate oxide layer, a polycrystalline gate and a gate electrode, the polycrystalline gate is positioned in the gate oxide layer, and the gate electrode is positioned on the upper surface of the polycrystalline gate and connected with the polycrystalline gate; p-type heavily doped regions are arranged on the left upper portion and the right upper portion of the N-type base region, an N-type heavily doped region is arranged on the surface layer in the N-type base region, and the portions, located in the P-type heavily doped regions, of the N-type heavily doped regions are separated by an etching process.

Further, a P-type base region is formed in the middle of the groove-shaped gate region.

And furthermore, a P-type heavily doped region is arranged at the middle upper part in the P-type base region.

Furthermore, an oxide layer is arranged on the upper layer of the N-type base region, and the part of the oxide layer, which is positioned in the P-type deep doping region, is separated by an etching process.

Still further, the surface of the oxide layer is covered with a metal layer.

Furthermore, a P + collector region is arranged on the lower surface of the N-type base region.

Still further, an N + field stop layer is arranged on the upper layer of the P + collector region.

Further, an emitter is arranged on the upper surface of the metal layer and connected with the metal layer.

Still further, the lower surface of P + collector region is provided with the collector.

The utility model discloses the advantage of structure lies in:

1. the utility model discloses the structure P type heavily mixes the district, is not connected with slot shape gate region, opens the in-process at the grid pressurization, is difficult for forming the inversion channel of connecting P type base region and P type heavily mixes the district below the slot, and the superficial empty potential in P type heavily mixes the district diminishes at opening the in-process rate of change, consequently reduces the influence to the gate region, has improved gate voltage's stability.

2. The utility model discloses the structure N type heavy doping district pushes away knot technology again through general notes, does not need extra photoetching board to form N type heavy doping district, is located the inside top layer of N-type base region, and its part that is located P type deep doping district is separated by the sculpture technology. Because the inversion channel of the N-type heavily doped region connecting the P-type base region and the P-type deeply doped region is arranged between the P-type base region and the P-type deeply doped region, the inversion channel connecting the P-type base region and the P-type deeply doped region is more difficult to form, and the floating potential of the P-type deeply doped region has small change rate in the starting process, the influence on the gate region is reduced, and the stability of the gate voltage is improved.

Drawings

Fig. 1 is a schematic diagram of a prior art structure.

Fig. 2 is a schematic structural diagram of the present invention.

In the drawings:

the semiconductor device comprises a 101-N-type base region, a 102-P-type base region, a 103-P-type heavily doped region, a 104-N-type heavily doped region, a 105-polycrystalline gate, a 106-gate oxide layer, a 107-oxide layer, a 108-metal layer, a 109-P-type deeply doped region, a 110-N + field stop layer, a 111-P + collector region, a G-gate electrode, an E-emitter and a C-collector.

Detailed Description

Example 1

An IGBT device structure capable of improving opening controllability comprises an N-type base region 101, wherein a groove-type gate region is arranged in the N-type base region 101 and comprises a gate oxide layer 106, a polycrystalline gate 105 and a gate electrode G, the polycrystalline gate 105 is located in the gate oxide layer 106, and the gate electrode G is located on the upper surface of the polycrystalline gate 105 and connected with the polycrystalline gate 105; p-type heavily doped regions 103 are arranged on the left upper portion and the right upper portion of the N-type base region 101, an N-type heavily doped region 104 is arranged on the surface layer in the N-type base region 101, and the portions, located in the P-type deeply doped region 109, of the N-type heavily doped region are separated through an etching process. The utility model discloses the structure P type heavily mixes district 109, is not connected with slot shape gate region, opens the in-process at the grid pressurization, is difficult for forming the inversion channel of connecting P type base region 102 and P type heavily mixes district 109 below the slot, and the superficial empty potential in the in-process change rate of opening of P type heavily doped district 109 diminishes, consequently reduces the influence to the gate region, has improved gate voltage's stability.

Example 2

An IGBT device structure capable of improving opening controllability comprises an N-type base region 101, wherein a groove-type gate region is arranged in the N-type base region 101 and comprises a gate oxide layer 106, a polycrystalline gate 105 and a gate electrode G, the polycrystalline gate 105 is located in the gate oxide layer 106, and the gate electrode G is located on the upper surface of the polycrystalline gate 105 and connected with the polycrystalline gate 105; p-type heavily doped regions 103 are arranged on the left upper portion and the right upper portion of the N-type base region 101, an N-type heavily doped region 104 is arranged on the surface layer in the N-type base region 101, and the portions, located in the P-type deeply doped region 109, of the N-type heavily doped region are separated through an etching process.

And a P-type base region 102 is formed in the middle of the groove-shaped gate region. The middle-upper part inside the P-type base region 102 is provided with a P-type heavily doped region 103.

An oxide layer 107 is arranged on the upper layer of the N-type base region 101, and the part of the oxide layer 107, which is positioned in the P-type deep doped region 109, is separated by an etching process. The surface of the oxide layer 107 is covered with a metal layer 108.

The lower surface of the N-type base region 101 is provided with a P + collector region. And an N + field stop layer is arranged on the upper layer of the P + collector region.

The upper surface of the metal layer 108 is provided with an emitter E, which is connected to the metal layer 108. And a collector C is arranged on the lower surface of the P + collector region.

The utility model discloses the structure P type heavily mixes district 109, is not connected with slot shape gate region, opens the in-process at the grid pressurization, is difficult for forming the inversion channel of connecting P type base region 102 and P type heavily mixes district 109 below the slot, and the superficial empty potential in the in-process change rate of opening of P type heavily doped district 109 diminishes, consequently reduces the influence to the gate region, has improved gate voltage's stability.

The utility model discloses the structure N type heavily doped region 104 pushes away the knot technology again through general notes, does not need extra photoetching board to form N type heavily doped region 104, is located the inside top layer of N-type base region 101, and its part that is located P type heavily doped region 109 is separated by the sculpture technology. Because the inversion channel formed by connecting the N-type heavily doped region 104 with the P-type base region 102 and the P-type deeply doped region 109 is arranged between the P-type base region 102 and the P-type deeply doped region 109, the inversion channel connected with the P-type base region 102 and the P-type deeply doped region 109 is more difficult to form, and the floating potential of the P-type deeply doped region 109 is reduced in change rate in the starting process, the influence on a gate region is reduced, and the stability of gate voltage is improved.

As shown in fig. 2, the N-type base region 101 is included, a trench-type gate region is arranged in the N-type base region 101, the trench-type gate region is located in the N-type base region 101 and includes a gate oxide layer 106, a polycrystalline gate 105 and a gate electrode G, the polycrystalline gate 105 is located inside the gate oxide layer 106, and the gate electrode G is located on the upper surface of the polycrystalline gate 105 and connected to the polycrystalline gate 105. A P-type base region 102 is arranged in the N-type base region 101, and the P-type base region 102 is positioned in the middle of the groove-shaped gate region. A P-type heavily doped region 103 is arranged in the N-type base region 101, and the P-type heavily doped region 103 is positioned at the middle upper part inside the P-type base region 102. P-type deep doping regions 109 are arranged in the N-type base region 101, and the P-type deep doping regions 109 are located at the left upper portion and the right upper portion of the N-type base region 101. An N-type heavily doped region 104 is arranged in the N-type base region 101, the N-type heavily doped region 104 is positioned on the surface layer in the N-type base region 101, and the part of the N-type heavily doped region 104 positioned in the P-type deeply doped region 109 is separated by an etching process. The oxide layer 107 is located on the upper layer of the N-base region, the part of the oxide layer located in the P-type deep doped region 109 is separated by the etching process, and the metal layer 108 covers the surface of the oxide layer 107. The P + collector region is positioned on the lower surface of the N-type base region 101, and the N + field stop layer is positioned on the upper layer of the P + collector region.

Claims

1. The utility model provides an improve IGBT device structure of opening controllability which characterized in that: the polycrystalline silicon-based gate structure comprises an N-type base region (101), wherein a groove-type gate region is arranged in the N-type base region (101), the groove-type gate region comprises a gate oxide layer (106), a polycrystalline gate (105) and a gate electrode (G), the polycrystalline gate (105) is positioned in the gate oxide layer (106), and the gate electrode (G) is positioned on the upper surface of the polycrystalline gate (105) and connected with the polycrystalline gate (105); p-type heavily doped regions (103) are arranged on the left upper portion and the right upper portion of the N-type base region (101), an N-type heavily doped region (104) is arranged on the surface layer in the N-type base region (101), and the portions, located in the P-type heavily doped region (109), of the N-type heavily doped region are separated through an etching process.

2. The IGBT device structure capable of improving opening controllability according to claim 1, wherein: and a P-type base region (102) is formed in the middle of the groove-shaped gate region.

3. The IGBT device structure capable of improving opening controllability according to claim 2, wherein: the middle-upper part inside the P-type base region (102) is provided with a P-type heavily doped region (103).

4. The IGBT device structure capable of improving opening controllability according to claim 1, wherein: an oxide layer (107) is arranged on the upper layer of the N-type base region (101), and the part of the oxide layer (107) located in the P-type deep doping region (109) is separated by an etching process.

5. The IGBT device structure capable of improving opening controllability according to claim 4, wherein: the surface of the oxide layer (107) is covered with a metal layer (108).

6. The IGBT device structure capable of improving opening controllability according to claim 1, wherein: the lower surface of the N-type base region (101) is provided with a P + collector region.

7. The IGBT device structure capable of improving opening controllability according to claim 6, wherein: and an N + field stop layer is arranged on the upper layer of the P + collector region.

8. The IGBT device structure capable of improving opening controllability according to claim 5, wherein: and an emitter (E) is arranged on the upper surface of the metal layer (108), and the emitter is connected with the metal layer (108).

9. The IGBT device structure capable of improving opening controllability according to claim 6, wherein: and a collector (C) is arranged on the lower surface of the P + collector region.