阅读说明：本技术 一种igbt功率器件有源层的制造方法及其结构 (Manufacturing method and structure of active layer of IGBT power device ) 是由 王丕龙 王新强 杨玉珍 张永利 刘�文 于 2021-08-19 设计创作，主要内容包括：本发明提供了一种IGBT功率器件有源层的制造方法及其结构,属于半导体集成电路制造技术领域,该一种IGBT功率器件有源层的制造方法包括步骤S1,提供一衬底,利用外延生长法在半导体衬底的上表面依次生长形成N型区和P型区；步骤S2,采用离子注入工艺在P型区上形成对称的掺杂N型层；步骤S3,采用刻蚀工艺在掺杂N型层刻蚀出第一沟槽,并利用离子注入工艺在第一沟槽内形成掺杂P型层；步骤S4,采用刻蚀工艺在掺杂P型层刻蚀出第二沟槽,并利用离子注入工艺在第二沟槽分别形成P+接触区和N+接触区；位置形成对称的薄膜接触层、接触孔和沟槽栅极,改善了IGBT有源区场强均匀性,从而提高了IGBT在该处抗动态雪崩能力。(The invention provides a manufacturing method and a structure of an active layer of an IGBT power device, belonging to the technical field of semiconductor integrated circuit manufacturing, the manufacturing method of the active layer of the IGBT power device comprises a step S1 of providing a substrate, and forming an N-type area and a P-type area on the upper surface of the semiconductor substrate by using an epitaxial growth method; step S2, forming a symmetrical N-type doped layer on the P-type region by adopting an ion implantation process; step S3, etching a first groove on the doped N-type layer by adopting an etching process, and forming a doped P-type layer in the first groove by utilizing an ion implantation process; step S4, etching a second groove on the doped P type layer by adopting an etching process, and respectively forming a P + contact area and an N + contact area on the second groove by utilizing an ion implantation process; the symmetrical thin film contact layer, the contact hole and the groove grid are formed at the position, the field intensity uniformity of the IGBT active area is improved, and therefore the dynamic avalanche resistance of the IGBT at the position is improved.)

1. A manufacturing method of an active layer of an IGBT power device is characterized by comprising the following steps:

step S1, providing a substrate, and forming an N-type region and a P-type region on the upper surface of the semiconductor substrate by epitaxial growth;

step S2, forming a symmetrical N-type doped layer on the P-type region by adopting an ion implantation process;

step S3, etching a first groove on the doped N-type layer by adopting an etching process, and forming a doped P-type layer in the first groove by utilizing an ion implantation process;

step S4, etching a second groove on the doped P type layer by adopting an etching process, and respectively forming a P + contact area and an N + contact area on the second groove by utilizing an ion implantation process;

step S5, depositing and photoetching metal, and forming metal electrodes on the upper surfaces of the P + contact area and the N + contact area;

and step S6, sintering and forming boron-phosphorus-silicon glass between the N-doped layers.

2. The method of claim 1, further comprising a step S7 of etching a third trench and a fourth trench in the borophosphosilicate glass and the P-type region respectively by an etching process.

3. The method for manufacturing the active layer of the IGBT power device according to claim 2, further comprising step S8, and then growing a thin film contact layer on the side wall of the third trench.

4. The method of claim 3, further comprising a step S9 of performing ion implantation in the third trench and the third trench by an ion implantation process to form a contact implantation region and a contact hole.

5. The method as claimed in claim 4, further comprising step S10, etching a fifth trench between the contact holes by an etching process, and forming a trench gate in the fifth trench by an ion implantation process.

6. The method of claim 5, further comprising step S11, wherein a surface metal is deposited between the metal electrodes to form the active layer.

7. The method as claimed in claim 1, wherein the step S8 is carried out by high temperature chemical vapor deposition, and the high temperature reaction temperature is 3000-4000 ℃.

8. The method for manufacturing the active layer of the IGBT power device according to claim 1, wherein the doping concentration range of the doped P type layer is 10¹⁰～10¹²cm^-3The doping impurity is arsenic, the energy is 80-160 kev, and the doping concentration range of the N-type doping layer is 10¹⁷～10¹⁹cm^-3The doping impurity is boron, and the energy is 200 to 300 kev.

9. The method for manufacturing the active layer of the IGBT power device according to claim 1, wherein the sintering temperature in the step S6 is in a range of 900-1200 ℃.

10. The structure of the active layer of the IGBT power device is applied to the manufacturing method of the active layer of the IGBT power device, which is characterized by comprising a substrate and an active layer, wherein the active layer is positioned on the upper surface of the substrate;

the active layer comprises an N-type region, a P-type region, a doped N-type layer, a doped P-type layer, a P + contact region, an N + contact region, a metal electrode, boron-phosphorus-silicon glass, a contact injection region, a thin film contact layer, a contact hole, a groove grid and surface layer metal, the P-type region is arranged above the N-type region, the number of the doped P-type layers is two, the two doped P-type layers are symmetrically arranged above the P-type region, the doped P-type layer is arranged inside the two doped P-type layers, the P + contact region and the N + contact region are arranged inside the doped P-type layer, the metal electrode is arranged above the P + contact region and the N + contact region, the boron-phosphorus-silicon glass is arranged between the two doped N-type layers, the contact hole is symmetrically arranged inside the boron-phosphorus-silicon glass, the thin film contact layer is arranged inside the contact hole, A groove grid is arranged below the groove grid, and surface layer metal is arranged between the two metal electrodes.

Technical Field

The invention belongs to the technical field of semiconductor integrated circuit manufacturing, and particularly relates to a manufacturing method and a structure of an active layer of an IGBT power device.

Background

An IGBT (Insulated Gate Bipolar transistor) is a new type of power semiconductor device. Has become a new generation of mainstream products in the field of power electronics. It is a MOS and bipolar combined device with MOS input and bipolar output functions.

Structurally, the high-power integrated device is composed of thousands of repeating units (namely the unit cells shown in figure 1) and is manufactured by adopting large-scale integration technology and power device technology. 10 is the trench gate thereof, 12 is the collector region of the IGBT, 9 is the source region (emitter region) thereof, and contact holes 2 connect the P-type body region 4 with the surface layer metal 1. The IGBT has the characteristics of high voltage, large current and high speed which are not fully possessed by other power devices. The bipolar power transistor has the advantages of high input impedance, small control power, simple driving circuit and high switching speed of the MOSFET, and also has the advantages of large current density, low saturation voltage and strong current processing capability of the bipolar power transistor. It is an ideal switch device in the field of power electronics.

At present, dynamic avalanche is easily generated in a field strong large area in an active area, so that the reliability of the IGBT is reduced, the transmission speed of the grid voltage of the IGBT is reduced, and the switching speed of the IGBT is reduced.

Disclosure of Invention

The embodiment of the invention provides a manufacturing method and a structure of an active layer of an IGBT (insulated gate bipolar transistor) power device, aiming at solving the problem that the existing active region is easy to generate dynamic avalanche in a region with larger field strength.

In view of the above problems, the technical solution proposed by the present invention is:

a manufacturing method of an active layer of an IGBT power device comprises the following steps:

step S1, providing a substrate, and forming an N-type region and a P-type region on the upper surface of the semiconductor substrate by epitaxial growth;

step S2, forming a symmetrical N-type doped layer on the P-type region by adopting an ion implantation process;

step S3, etching a first groove on the doped N-type layer by adopting an etching process, and forming a doped P-type layer in the first groove by utilizing an ion implantation process;

step S4, etching a second groove on the doped P type layer by adopting an etching process, and respectively forming a P + contact area and an N + contact area on the second groove by utilizing an ion implantation process;

step S5, depositing and photoetching metal, and forming metal electrodes on the upper surfaces of the P + contact area and the N + contact area;

and step S6, sintering and forming boron-phosphorus-silicon glass between the N-doped layers.

As a preferred technical solution of the present invention, the method further includes step S7, in which an etching process is used to etch a third trench and a fourth trench in the borophosphosilicate glass and the P-type region, respectively.

As a preferred embodiment of the present invention, the method further includes step S8, and then growing a thin film contact layer on the sidewall of the third trench.

As a preferred embodiment of the present invention, the method further includes step S9, performing ion implantation in the third trench and the third trench by using an ion implantation process to form a contact implantation region and a contact hole.

As a preferred technical solution of the present invention, the method further includes step S10, etching a fifth trench between the contact holes by using an etching process, and forming a trench gate in the fifth trench by using an ion implantation process.

In a preferred embodiment of the present invention, the method further includes step S11, depositing a surface metal between the metal electrodes to form a surface metal layer, and finally forming an active layer.

As a preferred technical solution of the present invention, in the step S8, the growth is performed by a high temperature chemical vapor deposition method, and the high temperature reaction temperature range is 3000-4000 ℃.

As a preferred embodiment of the present invention, the doping concentration range of the doped P-type layer is 10¹⁰～10¹²cm^-3The doped impurity is arsenic, the energy is 80 to 160kev,the doping concentration range of the N-doped layer is 10¹⁷～10¹⁹cm^-3The doping impurity is boron, and the energy is 200 to 300 kev.

In a preferred embodiment of the present invention, the sintering temperature in step S6 ranges from 900 ℃ to 1200 ℃.

On the other hand, the invention also provides a structure of an active layer of the IGBT power device, which comprises a substrate and an active layer, wherein the active layer is positioned on the upper surface of the substrate;

the active layer comprises an N-type region, a P-type region, a doped N-type layer, a doped P-type layer, a P + contact region, an N + contact region, a metal electrode, boron-phosphorus-silicon glass, a contact injection region, a thin film contact layer, a contact hole, a groove grid and surface layer metal, the P-type region is arranged above the N-type region, the number of the doped P-type layers is two, the two doped P-type layers are symmetrically arranged above the P-type region, the doped P-type layer is arranged inside the two doped P-type layers, the P + contact region and the N + contact region are arranged inside the doped P-type layer, the metal electrode is arranged above the P + contact region and the N + contact region, the boron-phosphorus-silicon glass is arranged between the two doped N-type layers, the contact hole is symmetrically arranged inside the boron-phosphorus-silicon glass, the thin film contact layer is arranged inside the contact hole, A groove grid is arranged below the groove grid, and surface layer metal is arranged between the two metal electrodes.

Compared with the prior art, the invention has the beneficial effects that:

(1) and a symmetrical doped N-type layer, a doped P-type layer, a P + contact region and an N + contact region are formed in the P-type region, so that high device breakdown voltage and low on-state voltage drop/resistance characteristics can be obtained, and a bidirectional symmetrical electric field cut-off device is formed.

(2) The symmetrical thin film contact layer, the contact hole and the groove grid are formed at the position, the field intensity uniformity of the IGBT active area is improved, and therefore the dynamic avalanche resistance of the IGBT at the position is improved.

The foregoing description is only an overview of the technical solutions of the present invention, and the embodiments of the present invention are described below in order to make the technical means of the present invention more clearly understood and to make the above and other objects, features, and advantages of the present invention more clearly understandable.

Drawings

FIG. 1 is a process flow diagram of a method for manufacturing an active layer of an IGBT power device disclosed by the invention

Fig. 2 to 14 are schematic structural diagrams of steps S1 to S11 of the method for manufacturing an active layer of an IGBT power device disclosed by the present invention.

Description of reference numerals: 1. a substrate; 2. an active layer; 3. an N-type region; 4. a P-type region; 5. doping an N-type layer; 6. doping a P type layer; 61. a first trench; 7. a P + contact region; 8. an N + contact region; 81. a second trench; 9. a metal electrode; 10. boron phosphorus silicon glass; 11. contacting the implanted region; 111. a third trench; 12. a thin film contact layer; 13. a contact hole; 131. a fourth trench; 14. a trench gate; 15. and (4) surface layer metal.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings of the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the equipment or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments.

Example one

Referring to the attached drawings 1-14, the invention provides a technical scheme that: a manufacturing method of an active layer of an IGBT power device comprises the following steps:

in step S1, a substrate is provided, and an N-type region and a P-type region are sequentially grown on the upper surface of the semiconductor substrate by epitaxial growth.

Step S2, forming a symmetrical N-type doped layer on the P-type region by adopting an ion implantation process, wherein the doping concentration range of the N-type doped layer is 10¹⁷cm^-3The doping impurity is boron, and the energy is 200 kev.

Step S3, etching a first trench on the N-doped layer by using an etching processAnd forming a doped P-type layer in the first trench by ion implantation process, wherein the doped concentration range of the doped P-type layer is 10¹⁰The doping impurity is arsenic, and the energy is 80 kev.

And step S4, etching a second groove on the doped P type layer by adopting an etching process, and respectively forming a P + contact region and an N + contact region in the second groove by utilizing an ion implantation process.

Step S5, depositing and photoetching metal to form metal electrodes on the upper surfaces of the P + contact region and the N + contact region.

And step S6, sintering the doped N-type layers to form boron-phosphorus-silicon glass, wherein the sintering temperature is 900 ℃.

And step S7, etching a third groove and a fourth groove on the borophosphosilicate glass and the P-type region respectively by adopting an etching process.

Step S8, a thin film contact layer is formed on the sidewall of the third trench by high temperature chemical vapor deposition, wherein the high temperature reaction temperature is 3000 ℃.

In step S9, ion implantation is performed on the third trench and the third trench by using an ion implantation process to form a contact implantation region and a contact hole.

And step S10, etching a fifth groove between the contact holes by adopting an etching process. And forming a trench gate in the fifth trench by using an ion implantation process.

In step S11, a surface metal is deposited between the metal electrodes to form an active layer.

Example two

Referring to the attached drawings 1-14, the invention provides a technical scheme that: a manufacturing method of an active layer of an IGBT power device comprises the following steps:

in step S1, a substrate is provided, and an N-type region and a P-type region are sequentially grown on the upper surface of the semiconductor substrate by epitaxial growth.

Step S2, forming a symmetrical N-type doped layer on the P-type region by adopting an ion implantation process, wherein the doping concentration range of the N-type doped layer is 10¹⁸cm^-3The doping impurity is boron, and the energy is 250 kev.

In the step of S3,etching a first groove on the doped N-type layer by adopting an etching process, and forming a doped P-type layer in the first groove by utilizing an ion implantation process, wherein the doping concentration range of the doped P-type layer is 10¹¹The doping impurity is arsenic, and the energy is 120 kev.

And step S4, etching a second groove on the doped P type layer by adopting an etching process, and respectively forming a P + contact region and an N + contact region in the second groove by utilizing an ion implantation process.

Step S5, depositing and photoetching metal to form metal electrodes on the upper surfaces of the P + contact region and the N + contact region.

And step S6, sintering the doped N-type layers to form boron-phosphorus-silicon glass, wherein the sintering temperature is 1000 ℃.

And step S7, etching a third groove and a fourth groove on the borophosphosilicate glass and the P-type region respectively by adopting an etching process.

Step S8, a thin film contact layer is formed on the sidewall of the third trench by high temperature chemical vapor deposition, wherein the high temperature reaction temperature range is 3500 ℃.

In step S9, ion implantation is performed on the third trench and the third trench by using an ion implantation process to form a contact implantation region and a contact hole.

And step S10, etching a fifth groove between the contact holes by adopting an etching process. And forming a trench gate in the fifth trench by using an ion implantation process.

In step S11, a surface metal is deposited between the metal electrodes to form an active layer.

EXAMPLE III

Referring to the attached drawings 1-14, the invention provides a technical scheme that: a manufacturing method of an active layer of an IGBT power device comprises the following steps:

in step S1, a substrate is provided, and an N-type region and a P-type region are sequentially grown on the upper surface of the semiconductor substrate by epitaxial growth.

Step S2, forming a symmetrical N-type doped layer on the P-type region by adopting an ion implantation process, wherein the doping concentration range of the N-type doped layer is 10¹⁹cm^-3Doping impurity of boron with energyIs 300 kev.

Step S3, etching a first trench on the doped N-type layer by using an etching process, and forming a doped P-type layer in the first trench by using an ion implantation process, wherein the doped concentration range of the doped P-type layer is 10¹²The doping impurity is arsenic, and the energy is 160 kev.

And step S4, etching a second groove on the doped P type layer by adopting an etching process, and respectively forming a P + contact region and an N + contact region in the second groove by utilizing an ion implantation process.

Step S5, depositing and photoetching metal to form metal electrodes on the upper surfaces of the P + contact region and the N + contact region.

And step S6, sintering the doped N-type layer to form boron-phosphorus-silicon glass, wherein the sintering temperature is 1200 ℃.

And step S7, etching a third groove and a fourth groove on the borophosphosilicate glass and the P-type region respectively by adopting an etching process.

Step S8, a thin film contact layer is formed on the sidewall of the third trench by high temperature chemical vapor deposition, wherein the high temperature reaction temperature is 4000 ℃.

In step S9, ion implantation is performed on the third trench and the third trench by using an ion implantation process to form a contact implantation region and a contact hole.

And step S10, etching a fifth groove between the contact holes by adopting an etching process. And forming a trench gate in the fifth trench by using an ion implantation process.

In step S11, a surface metal is deposited between the metal electrodes to form an active layer.

Example four

Referring to fig. 14, an embodiment of the present invention further provides a structure of an active layer of an IGBT power device, including a substrate and an active layer, where the active layer is located on an upper surface of the substrate, the active layer includes an N-type region, a P-type region, two doped N-type layers, two doped P-type layers, two P + contact regions, two N + contact regions, a metal electrode, borophosphosilicate glass, a contact implantation region, a thin film contact layer, a contact hole, a trench gate, and a surface metal, the P-type regions are located above the N-type region, the two doped P-type layers are symmetrically disposed above the P-type region, the doped P-type layers are disposed inside the two doped P-type layers, the P + contact regions and the N + contact regions are disposed inside the doped P-type layers, the metal electrode is disposed above the P + contact regions and the N + contact regions, borophosphosilicate glass is disposed between the two doped N-type layers, the contact holes are symmetrically disposed inside the borophosphosilicate glass, the contact hole is internally provided with a film contact layer, a groove grid is arranged below the contact hole, and surface layer metal is arranged between the two metal electrodes.

One or more technical solutions in the embodiments of the present application have at least one or more of the following technical effects:

(1) and a symmetrical doped N-type layer, a doped P-type layer, a P + contact region and an N + contact region are formed in the P-type region, so that high device breakdown voltage and low on-state voltage drop/resistance characteristics can be obtained, and a bidirectional symmetrical electric field cut-off device is formed.

(2) The symmetrical thin film contact layer, the contact hole and the groove grid are formed at the position, the field intensity uniformity of the IGBT active area is improved, and therefore the dynamic avalanche resistance of the IGBT at the position is improved.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.