CN106229313B - Power device and preparation method thereof - Google Patents

Abstract

The present disclosure provides power devices and methods of making the same. The power device includes: a first device having a plurality of first source regions and having a plurality of first trenches, wherein the plurality of first trenches electrically isolate the plurality of first source regions from each other; at least one second device having a plurality of second source regions and having a plurality of second trenches electrically isolating the plurality of second source regions from each other, the second device being embedded in the first device and the second trenches of the second device communicating with the respective first trenches of the first device, wherein the second source regions of the second device are electrically isolated from the first source regions of the first device by metal spacer regions, and wherein portions of the body regions of the first and second devices other than the trenches are active regions. According to the power device and the preparation method thereof disclosed by the invention, the embedding of the second device does not cause structural change to the first device, so that the current-voltage performance of the first device is not affected.

Description

Power device and manufacturing method thereof

technical field

The present disclosure relates to the field of semiconductors, in particular to a power device and a manufacturing method thereof.

Background technique

For power devices, in order to monitor the working status of the device, it is necessary to quantitatively (usually reduce a proportional factor according to the current of the main device, and this coefficient is generally expressed in CSR) to measure the current conducted by the device in a timely and full range to ensure the safety of the device Reliable, such as in the field of automotive electronics. Traditionally, a current sensing device, such as a current mirror device, can be coupled in at an appropriate location within the overall device (called a master device) to provide this measurement. Coupling and isolation of the current sensing device from the host device is very important.

Contents of the invention

According to an aspect of the present disclosure, there is provided a power device, including: a first device having a plurality of first source regions and a plurality of first trenches, wherein the plurality of first trenches connect a plurality of The first source regions are electrically isolated from each other; at least one second device, the second device has a plurality of second source regions and has a plurality of second trenches, and the plurality of second trenches electrically isolates the plurality of second source regions from each other, Wherein the second device is embedded in the first device, and the second trench of the second device communicates with the corresponding first trench of the first device, wherein, the second source region of the second device communicates with the first device The first source region is electrically isolated by the metal spacer region, and the body regions of the first device and the second device except the trench are all active regions.

According to an aspect of the present disclosure, a method for fabricating a power device is provided, including: providing a substrate; forming a body region of a first device and a body region of at least one second device on the substrate; A plurality of first trenches for the first device are formed in the body region of the second device, and a plurality of second trenches for the second device are formed in the body region of the second device, wherein the second trenches of the second device are connected to the first The corresponding first trenches of the devices are connected; forming a plurality of first source regions for the first device and a plurality of second source regions for the second device, wherein the plurality of first source regions pass through the plurality of first source regions A trench is electrically isolated from each other, and a plurality of second source regions are electrically isolated from each other through the plurality of second trenches; wherein, the second source region of the second device and the first source region of the first device are separated by a metal spacer region Electrically isolated, and wherein the body regions of the first device and the second device are active regions except for the trenches.

According to the power device and its manufacturing method of the present disclosure, the first device and the second device are coupled and isolated in a unique manner, and since the part where the second device and the first device are embedded does not have another high-concentration diffusion region (that is, there is no source region), the embedding of the second device is smooth and does not cause structural changes to the first device, and therefore does not cause any adverse effects on the current-voltage performance of the first device. In addition, the embedded part of the second device and the first device has no desource region, so this part can still contribute to the current supply, so that no chip area is wasted.

Description of drawings

The features and advantages of the present invention will be more clearly understood by reference to the accompanying drawings, which are schematic and should not be construed as limiting the disclosure in any way, in which:

FIG. 1 is a simplified plan view illustrating a power device according to an exemplary embodiment of the present disclosure;

FIG. 2 is a plan view illustrating details of a power device according to an exemplary embodiment of the present disclosure;

Fig. 3-Fig. 5 shows the sectional view along A-A, B-B, C-C in Fig. 2 respectively;

FIG. 6 is a plan view illustrating details of a power device according to an exemplary embodiment of the present disclosure;

Fig. 7-Fig. 8 shows the sectional view along D-D, E-E in Fig. 6 respectively;

Fig. 9 is a sectional view showing positions 601-603 in Fig. 6;

FIG. 10 is a plan view illustrating details of a power device according to an exemplary embodiment of the present disclosure;

Fig. 11-Fig. 13 respectively show the sectional view along F-F, G-G, H-H in Fig. 10;

Figure 14 is a sectional view showing position 1001 in Figure 10; and

FIG. 15 is a flowchart illustrating a method of manufacturing a power device according to an exemplary embodiment of the present disclosure.

Detailed ways

The following detailed description of the embodiments of the present disclosure covers numerous specific details in order to provide a thorough understanding of the embodiments of the present disclosure. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some of these specific details. The following description of the embodiments is only to provide a clearer understanding of the present invention by showing examples of the present invention. The present invention is by no means limited to any specific configuration set forth below, but covers any modifications, substitutions and improvements of related elements and parts without departing from the spirit of the present invention.

The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to limit the invention to any theory expressed or implied by the preceding technical field, background or the following detailed description.

The abbreviations "MOSFET" and "IGBT" are used in this disclosure to refer to Metal Oxide Semiconductor Field Effect Transistor and Insulated Gate Bipolar Transistor, respectively. MOSFETs and IGBTs have conductive gate electrodes, however it should be understood that the conductive material is not necessarily a metallic material, but can be, for example, metal alloys, semi-metals, metal-semiconductor alloys or compounds, doped semiconductors, combinations thereof. In this disclosure, references to "metal contacts" and the like should be broadly interpreted to include the various conductor forms discussed above and are not intended to be limited to metallized conductors only. Non-limiting examples of insulating materials suitable for use in MOSFETs and IGBTs are oxides, nitrides, oxygen nitrogen mixtures, organic insulating materials, and other dielectrics.

For simplicity and clarity of illustration, the drawings illustrate the general manner of construction, and descriptions and details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the present invention. Additionally, elements in the drawings are not necessarily drawn to scale. For example, the size of some of the elements or regions in the figures may be exaggerated relative to other elements or regions to help to improve the understanding of the embodiments of the invention.

Ordinal numerals such as "first", "second", "third", "fourth" in the description and claims may be used to distinguish between similar elements or steps and not necessarily to describe a specific sequence or sequence. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation or arrangement in sequences other than those illustrated or otherwise described herein . Furthermore, the terms "comprising", "comprising", "having" and variations thereof, are meant to cover non-exclusive inclusions such that a process, method, product or apparatus comprising a series of elements or steps is not necessarily limited to those elements or steps, but may include other elements or steps not explicitly listed or inherent to the process, method, product or apparatus. As used herein, the term "communication" is defined as a direct or indirect electrical or non-electrical connection. As used herein, the terms "substantial" and "substantially" mean sufficient in a practical manner to accomplish the stated purpose and that those minor defects, if any, are not apparent for the stated purpose Impact.

"Additionally" in the specification and claims means other than normal. For example "an additional high concentration diffusion" refers to a diffusion outside of the normal active area diffusion and at a concentration higher than the bulk concentration.

As used herein, the term "substrate" may refer to a semiconductor substrate, whether the semiconductor used is single crystal, polycrystalline or amorphous, and includes group IV semiconductors, non-group IV semiconductors, compound semiconductors, and organic and inorganic semiconductors, and may Examples are thin-film structures or laminated structures.

For ease of illustration and without limitation, silicon semiconductors are used herein to describe power devices and methods of making them, but those skilled in the art will understand that other semiconductor materials may also be used. In addition, various device types and/or doped semiconductor regions may be labeled N-type or P-type, but this is for convenience of illustration and not intended to be limiting, and such labels may be "first conductivity type" or "second, instead of the more general description of "opposite conductivity type", where the first conductivity type can be either N-type or P-type, and the second conductivity type can also be P-type or N-type.

According to an aspect of the present disclosure, there is provided a power device, including: a first device having a plurality of first source regions and a plurality of first trenches, wherein the plurality of first trenches A source region is electrically isolated from each other; at least one second device, the second device has a plurality of second source regions and has a plurality of second trenches, and the plurality of second trenches electrically isolates the plurality of second source regions from each other, wherein The second device is embedded in the first device, and the second trench of the second device communicates with the corresponding first trench of the first device, wherein the second source region of the second device communicates with the first trench of the first device. A source region is electrically isolated by the metal spacer region, and the body regions of the first device and the second device are all active regions except for the groove.

In one embodiment, a plurality of second source regions of the second device are concentratedly arranged.

In one embodiment, the first device and the second device are formed on a P+N substrate, and the power device is an insulated gate bipolar transistor. In one embodiment, the first device and the second device are formed on an N+N substrate, and the power device is a metal oxide semiconductor field effect transistor.

In one embodiment, each second source region of the second device corresponds to a corresponding one of the first source regions of the first device, and each second trench of the second device corresponds to a corresponding one of the first source regions of the first device. The trenches are directly connected. In an implementation manner, the power device further includes a plurality of third trenches, each third trench corresponds to a second source region of the second device, and two second source regions corresponding to the second source region The grooves are connected. The first trench, the second trench and the third trench are identical in structure. In another implementation, the first source region of the first device has a first metal contact region, the second source region of the second device has a second metal contact region, and the boundary of the first metal contact region is in contact with the corresponding second metal contact region. The boundaries of the zones are at such a distance that current can no longer flow laterally across the plane.

In one embodiment, each second source region of the second device corresponds to two corresponding first source regions of the first device, and the power device further includes a plurality of fourth trenches, and each fourth trench is in the form of Three-terminal shape, corresponding to a second source region of the second device, and connecting two second trenches corresponding to the second source region and two first source regions corresponding to the second source region The first trench is connected. The first groove, the second groove, and the fourth groove are identical in structure.

According to the power device and its manufacturing method of the present disclosure, the first device and the second device are coupled and isolated in a unique manner, and since the part where the second device is embedded with the first device does not have another high-concentration diffusion region (that is, there is no source region), the embedding of the second device is smooth and does not cause structural changes to the first device, and therefore does not cause any adverse effects on the current and voltage performance of the first device. In addition, the embedded part of the second device and the first device has no desource region, so this part can still contribute to the current supply, so that no chip area is wasted.

Embodiments according to the present invention will be described in more detail below with reference to the accompanying drawings.

FIG. 1 is a simplified plan view illustrating a power device 100 according to an exemplary embodiment of the present disclosure. As shown in FIG. 1 , a power device 100 includes a first device 1 and a second device 2 . In one example, the second device 2 may be a current sensing device, such as a mirror current device. The second device 2 is formed on the same substrate 3 as the first device 1, that is, the second device 2 and the first device 1 are coupled in the same chip, so that the second device 2 and the first device 1 can Under the same conditions (eg temperature). The substrate 3 may be a P+N substrate, whereby the power device 100 may be an insulated gate bipolar transistor (IGBT), or the substrate may be an N+N substrate, whereby the power device 100 may be a metal oxide semiconductor Field Effect Transistors (MOSFETs).

The second device 2 is embedded in the first device 1 , and the second device 2 is electrically isolated from the first device 1 . In essence, the second device 2 has a drain and a gate connected to the first device 1, except that the source region is electrically isolated. The second device 2 is electrically isolated from the first device 1 by a metal spacing region (not shown). That is to say, the source region of the second device 2 and the source region of the first device 1 can be electrically isolated by a certain distance between the source region metal.

As shown in FIG. 1 , the power device 100 further includes a gate electrode terminal 4 to which each gate of the first device 1 and the second device 2 is connected. Specifically, the polysilicon in each gate trench of the first device 1 and the second device 2 is connected to the gate electrode terminal 4 .

It should be understood that although the second device 2 is shown approximately in the center portion of the first device 1 and only one second device 2 is shown, this is only an example. The second device 2 can be located in any other position of the first device 1 , and more second devices 2 can also be arranged, which depends on the temperature distribution and specific requirements of the chip.

The total effective size area of the second device 2 (ie, the area of the metal source region) is scaled down (CSR) to the total effective size area of the first device 1 in order to obtain a current proportional to the current of the first device 1 . In this way, the current collected by the second device 2 can determine the amount of current conducted by the first device 1 , so as to monitor the state of the first device 1 .

FIG. 2 is a plan view showing details of a power device 200 according to one embodiment of the present disclosure. As shown in FIG. 2 , the power device 200 includes a first device 1 and a second device 2 . The second device 2 is embedded in the first device 1 , and the second device 2 is electrically isolated from the first device 1 by the metal spacing region 5 . As mentioned above, substantially the metal spacer region 5 electrically separates the source region of the second device 2 from the source region of the first device 1 . In FIG. 2 , the area outside the outer dotted line represents the metal 11 of the first device 1 , and the area inside the inner dotted line represents the metal 21 of the second device 2 . More precisely, the uppermost layer of the chip is a metal layer, and the area outside the outer dashed line is covered with the metal of the first device 1 , and the area inside the inner dashed line is covered with the metal of the second device 2 . The area between the two dotted lines is the metal spacing area 5, which separates the metal of the first device 1 from the metal of the second device 2, and accordingly separates the source area of the first device 1 from the source area of the second device 2 open. In the present disclosure, the metal spacing region 5 means that there is a certain distance between the metal 11 of the first device 1 and the metal 21 of the second device 2 .

Referring next to FIG. 2 , the first device 1 has a plurality of first source regions 12 each having its first metal contact 14 . The first device 1 collects current through these first source regions 12 during operation. Similarly, the second device 2 has a plurality of second source regions 22 , each first source region 22 having its second metal contact 24 . The second device 2 collects current through these second source regions 22 . The current collected by the second device 2 through all the second source regions 22 and the current collected by the first device 1 through all the first source regions 12 should have a predetermined proportional relationship. By measuring the current collected by the second device 2 , the amount of current conducted by the first device 1 can be determined, and then the state of the first device 1 can be monitored. It should be understood that these source regions 12 and 22 are actually located below the metal layer, which is illustrated hereinafter.

In addition, as shown in FIG. 2 , the first device 1 further includes a plurality of first trenches 13 . In one example, the first groove 13 may be a strip groove. These first trenches 13 electrically isolate the plurality of first source regions 12 of the first device 1 from each other. Similarly, the second device 2 also includes a plurality of second trenches 23 . In one example, the second groove 23 may be a strip groove. These second trenches 23 electrically isolate the plurality of second source regions 22 of the second device 2 from each other. As shown in FIG. 2 , the second trench 23 of the second device 2 communicates with the corresponding first trench 13 of the first device 1 . In essence, the first trench 13 and the second trench 23 are actually located in the body regions of the first device 1 and the second device 2 respectively, and the first trench 13 and the second trench 23 respectively correspond to the first device 1 The gate of the first device 1 is connected to the gate of the second device 2 , that is, the gate of the first device 1 is connected to the gate of the second device 2 .

In addition, as shown in FIG. 2, each second source region 22 of the second device 2 corresponds to a corresponding one of the first source regions 12 of the first device 1, and each second trench 23 of the second device 2 corresponds to A corresponding one of the first trenches 13 of the first device 1 is connected. The power device 200 also includes a plurality of third trenches 6. Each third trench 6 corresponds to a second source region 22 of the second device 2 , and connects two second trenches 23 corresponding to the second source region 22 . As shown in the figure, correspondingly, each third trench 6 also corresponds to a first source region 12 of the first device 1, and connects two first trenches 13 corresponding to the first source region 12 Pass. In one example, the third trench 6 may be located within the metal spacing region 5 . The third trench 6 not only functions as a gate, but also can fully isolate the source region 22 of the second device 2 from the corresponding source region 12 of the first device 1 . In one example, the third groove 6 may be a strip groove. The third trench 6 is identical to the first trench 13 and the second trench 23 in structure.

More specifically, the second source region 22 - 1 of the second device 2 corresponds to the corresponding one of the first source regions 12 - 1 of the first device 1 . The second trenches 23 - 1 and 23 - 2 of the second device 2 communicate with the corresponding first trenches 13 - 1 and 13 - 2 of the first device 1 , respectively. The third trench 6 corresponds to the second source region 22-1 of the second device 2, and connects the two second trenches 23-1 and 23-2 corresponding to the second source region 22-1. In addition, as shown in the figure, correspondingly, the third trench 6 also corresponds to the first source region 12-1 of the first device 1, and the two first trenches corresponding to the first source region 12-1 The grooves 13-1 and 13-2 are connected.

In addition, as shown in FIG. 2, although the multiple second source regions 22 of the second device 2 are separated by the second trenches 23, these second source regions are concentratedly arranged, that is, two adjacent second source regions Regions 22 are not separated from any other source regions. Although six source regions and corresponding metal contacts of the second device 2 are shown in FIG. A predetermined ratio CSR of the second device 2 to the first device 1 .

3-5 respectively show the sectional views along A-A, B-B, and C-C in FIG. 2 . Fig. 3 shows a sectional view along A-A in Fig. 2 . Referring back to FIG. 2, the A-A line crosses the metal region of the first device 1 and the metal region of the second device 2, and both ends of the A-A line are located exactly at the source region metal contact 14 of the first device 1 and the source region of the second device 2 metal contact 24 on. As shown in FIG. 3 , the first device 1 and the second device 2 are formed on the same substrate 3 . In one embodiment, the first device 1 and the second device 2 may be formed on a P+N type substrate or an N+N type substrate.

Furthermore, as shown in FIG. 3, on the substrate 3, an active region is formed. The active area is composed of N-type layer and P-type layer. Trenches 6 are formed in the active region. An N+ layer is formed on the P-type layer, and a P+ region is formed in the P-type layer and the N+ layer. An oxide layer 10 is deposited over the trench 6 filled with polysilicon. The two sides of the oxide layer 10 are the metal 11 of the first device 1 and the metal 21 of the second device 2 respectively, and the metal 11 of the first device 1 and the metal 21 of the second device 2 are separated by the metal spacing region 5, correspondingly , the source region 12 of the first device 1 and the source region 22 of the second device 2 are electrically isolated. The trench 6 filled with polysilicon not only serves to connect the gates of the first device 1 and the second device 2, but also helps to fully isolate the source region 12 of the first device 1 from the source region 22 of the second device 2 . The first device 1 and the second device 2 respectively collect their respective currents via their respective source regions through corresponding metal contacts 14 and 24 along arrows I1 and I2 representing current flow directions.

Fig. 4 shows a sectional view along B-B in Fig. 2 . Referring back to FIG. 2 , the B-B line crosses the metal 11 of the first device 1 and the metal 21 of the second device 2, and one end of the B-B line is just on the source region metal contact 14 of the first device 1, while the other end does not correspond to the second Source metal contact for device 2. Referring to FIG. 4 , the first device 1 and the second device 2 are formed on the same substrate 3 , and the metal 11 of the first device 1 is separated from the metal 21 of the second device 2 by a metal spacing region 5 . Since one end of the BB line is right on the metal contact 14 in the source region of the first device 1 , the first device 1 can collect current through the first metal contact 14 via the first source region. However, since the other end of the B-B line does not have a metal contact corresponding to the source region of the second device 2 , the second device 2 does not collect current there. As shown, the current in the region below the oxide layer 10 and the metal 21 of the second device 2 is collected by the first device 1 through the first metal contact 14 via the first source region.

Fig. 5 shows a sectional view along C-C in Fig. 2 . Referring back to FIG. 2 , the C-C line crosses the metal 11 of the first device 1 and the metal 21 of the second device 2 , and the C-C line is vertical and crosses 5 trenches. Referring to FIG. 5 , the first device 1 and the second device 2 are formed on the same substrate 3 , and the metal 11 of the first device 1 is electrically isolated from the metal 21 of the second device 2 by the metal spacing region 5 . The intermediate trench under the oxide layer 10 (ie in the metal spacing region) also helps to isolate the metal 11 of the first device 1 from the metal 21 of the second device 2 . In addition, one end of the CC line enters the metal region of the first device 1 and the other end enters the metal region of the second device 2 as it moves away from the middle trench. In the part of the first device 1, there are two other trenches 13, and the first metal contact 14 of the first source region exists between the two trenches, and the current passes through the metal contact in the part between the two trenches 13 14 were collected. On the other hand, in the part of the second device 2, there are also two trenches 23, and the second metal contact 24 of the second source region exists between the two trenches 23, and the part between the two trenches 23 , current is collected through the metal contact 24 . In this way, the first device 1 and the second device 2 respectively collect their own currents along the arrows I1 and I2 that indicate the current flow directions shown in the figure.

It should be noted that in the power device according to the embodiment of the present disclosure, the body regions of the second device 2 and the first device 1 except for the trenches are all active regions. That is to say, in addition to the second device 2 and the active region of the first device 1 itself, in the embedded part of the second device 2 and the first device 1 (including, for example, separating the source region of the second device 2 from the first device The part of the metal spacing region of the source region of 1, the source region part of the first device 1 under the metal of the second device 2 (the metal of the second device 2 on this part is the source lead-out line of the second device 2) ) has no additional high-concentration diffusion regions, ie, no desource regions. In this way, the embedding of the second device 2 is smooth and does not cause structural changes to the first device 1 , and therefore does not cause any adverse effects on the current and voltage performance of the first device 1 . In addition, since the embedded part of the second device 2 and the first device 1 has no de-source region, this part can still contribute to the current supply, so that no chip area is wasted.

FIG. 6 is a plan view illustrating a power second device 300 according to another exemplary embodiment of the present disclosure. As shown in FIG. 6 , the same as the power device 200 shown in FIG. 2 , the power device 300 includes a first device 1 and a second device 2 . The second device 2 is embedded in the first device 1 , and the second device 2 is isolated from the first device 1 by a metal spacing region 5 . Furthermore, the first device 1 has a plurality of source regions 12 and a plurality of trenches 13 . These first trenches 13 electrically isolate the metal contacts 12 of the first component 1 from each other. The second device 2 has a plurality of source regions 22 and a plurality of trenches 23 . These second trenches 23 electrically isolate the source regions 22 of the second device 2 from each other. In addition, similarly, the trench 23 of the second device 2 communicates with the trench 13 of the first device 1 , and the source regions 22 of the second device 2 are arranged in a concentrated manner.

The difference between the power device 300 in FIG. 6 and the power device 200 shown in FIG. 2 lies in the arrangement of source regions and trenches. Therefore, aspects and details consistent with the power device 200 shown in FIG. 2 will not be repeated here. The arrangement of the source region and the trench of the power device 300 will be discussed in detail below.

As shown in FIG. 6, in this exemplary embodiment, each second source region 22 of the second device 2 corresponds to two corresponding first source regions 12 of the first device 1, and the power device 22 also includes a plurality of Fourth trenches 7, each fourth trench 7 is three-terminal, corresponding to a second source region 22 of the second device 2, and the two second trenches corresponding to the second source region 22 23 communicates with the first trench 13 between the two first source regions 12 corresponding to the second source region 22 . More specifically, the source region 22-1 of the second device 2 has two corresponding second trenches 23-1 and 23-2, and is connected to the two first source regions 12-1 and 12-1 of the first device 1. 2 corresponds. There is a first trench 13-1 between the two first source regions 12-1 and 12-2. The fourth trench 7 is three-terminal, corresponding to the second source region 22-1, and connects the second trenches 23-1 and 23-2 with the first trench 13-1, wherein the three-terminal Two ends are connected to the second grooves 23-1 and 23-2 respectively, and the other end is connected to the first groove 13-1. In FIG. 8, specifically, the three-terminal shape is a T-shape. However, the three-terminal shape can be other shapes, such as a Y shape with any angle.

7-8 respectively show cross-sectional views along D-D and E-E in FIG. 6 . Fig. 7 shows a sectional view along D-D in Fig. 6 . Referring back to FIG. 6 , the D-D line spans the metal region of the first device 1 and the metal region of the second device 2 , and the position where the D-D line passes does not pass through any source metal contact. Referring to FIG. 7 , the first device 1 and the second device 2 are formed on the same substrate 3 , and the metal 11 of the first device 1 is separated from the metal 21 of the second device 2 by a metal spacing region 5 . A trench 7 is formed in the body region below the oxide layer 10 , and the trench 7 is used to connect the trench of the first device 1 and the trench of the second device 2 . Since the position where the D-D line passes does not pass through any source metal contact, there is no current representation in FIG. 7 .

FIG. 8 shows a sectional view along E-E in FIG. 6 . Referring back to FIG. 6 , the E-E line crosses the metal 11 of the first device 1 and the metal 21 of the second device 2 , and the E-E line is vertical and crosses 3 trenches. Referring to FIG. 8 , the first device 1 and the second device 2 are formed on the same substrate 3 , and the metal 11 of the first device 1 is electrically isolated from the metal 21 of the second device 2 by the metal spacing region 5 . The intermediate trench under the oxide layer 10 (ie in the metal spacing region) also helps to isolate the metal 11 of the first device 1 from the metal 21 of the second device 2 . In addition, one end of the EE line enters the metal region of the first device 1 and the other end enters the metal region of the second device 2 as it moves away from the middle trench. In the part of the first device 1, there is another trench 13, and at the left end of this trench there is a metal contact 14 of the first source region, through which the current is collected. On the other hand, in the part of the second device 2, there is another trench 23, and there is a metal contact 24 of the second source region at the right end of the trench 23, and the current is collected through the metal contact 24. In this way, the first device 1 and the second device 2 respectively collect their own currents along the arrows I1 and I2 that indicate the current flow directions shown in the figure.

FIG. 9 is a cross-sectional view showing different positions 601 - 602 in FIG. 6 . Referring back to FIG. 6 , the position 601 is located in the area of the first device 1 and spans the trench 13 and the source region metal contacts 14 on both sides; the position 602 is located in the area of the second device 2 and spans the T-shaped trench 7 The head portion, and one end is located on the metal contact of the source region of the second device 2 . Referring to Figure 9, cross-sectional views of locations 601 and 602 are shown in Figures (a) and (b) respectively. For the position 601 , the uppermost layer is covered with the metal 11 of the first device 1 . Since location 601 is located on trench 13 , trench 13 is illustrated in this view. The trench 13 is used to isolate the source region 12 of the first device 1 . Since the two ends of position 601 are located on the source region metal contact 14 of the first device 1, two metal contacts 14 are shown in Fig. The arrows I collect the respective currents.

For the position 602 , the uppermost layer is covered with the metal 21 of the first device 2 . Since location 602 spans trench 7 , trench 7 is illustrated in this view. The trench 7 is used to isolate the source region of the first device 1 from the source region of the second device 2 . Since one end of position 602 is located on the source region metal contact 24 of the second device 2, one metal contact 24 is illustrated in FIG. 9(b), and this metal contact 24 collects current along the arrow I representing the current flow. .

It should be noted that position 603 is also shown in FIG. 6 . The structure at position 603 is the same as the structure at position 601, except that the metal of the upper layer and the source region are in contact with the metal and source region of the second device 2, which are marked as 21 and 24 in FIG. 9(a), and in addition , the groove is marked 23 accordingly.

It should also be noted that, in the power device according to the embodiment of the present disclosure, the body regions of the second device 2 and the first device 1 except for the trenches are active regions. That is to say, in addition to the second device 2 and the active region of the first device 1 itself, in the embedded part of the second device 2 and the first device 1 (including, for example, separating the source region of the second device 2 from the first device The part of the metal spacing region of the source region of 1, the source region part of the first device 1 under the metal of the second device 2 (the metal of the second device 2 on this part is the source lead-out line of the second device 2) ) has no additional high-concentration diffusion regions, ie, no desource regions. In this way, the embedding of the second device 2 is smooth and does not cause structural changes to the first device 1 , and therefore does not cause any adverse effects on the current and voltage performance of the first device 1 . In addition, since the embedded part of the second device 2 and the first device 1 has no de-source region, this part can still contribute to the current supply, so that no chip area is wasted. FIG. 10 is a plan view illustrating a power device 400 according to another exemplary embodiment of the present disclosure. As shown in FIG. 10 , the same as the power device 200 shown in FIG. 2 , the power device 400 includes a first device 1 and a second device 2 . The second device 2 is embedded in the first device 1 , and the second device 2 is isolated from the first device 1 by a metal spacing region 5 . Furthermore, the first device 1 has a plurality of source regions 12 and a plurality of trenches 13 . These first trenches 13 electrically isolate the metal contacts 12 of the first component 1 from each other. The second device 2 has a plurality of second source regions 22 and a plurality of second trenches 23 . These second trenches 23 electrically isolate the source regions 22 of the second device 2 from each other. In addition, the second trench 23 of the second device 2 communicates with the first trench 13 of the first device 1 , and the source regions 22 of the second device 2 are concentratedly arranged.

The difference between the power device 400 in FIG. 10 and the power device 200 shown in FIG. 2 lies in the arrangement of source regions and trenches. Therefore, aspects and details consistent with the power device 200 shown in FIG. 2 will not be repeated here. The arrangement of the source region and the trench of the power device 400 will be discussed in detail below.

As shown in FIG. 10, in this exemplary embodiment, each second source region 22 of the second device 2 corresponds to a corresponding one of the first source regions 12 of the first device 1, and each second source region 22 of the second device 2 The second trench 23 communicates with a corresponding first trench 13 of the first device 1 . Different from the power device 200 , the power device 400 does not have the third trench 6 as shown in FIG. 2 . Instead, the metal contact 24 of the second source region 22 of the second device 2 is at a certain distance L from the metal contact 14 of the corresponding first source region 12 of the first device 1, so that current can no longer flow laterally along the plane, thereby Sufficient isolation of the source regions of the first device 1 and the second device 2 is achieved. In one example, the distance L may be between 10 μm and 50 μm. It should be understood that the smaller the distance, the better, as long as the purpose of preventing the current from moving laterally along the plane can be achieved.

Figures 11-14 show cross-sectional views along F-F, G-G, and H-H in Figure 10, respectively. Fig. 11 shows a cross-sectional view along F-F in Fig. 10 . Referring back to FIG. 10 , the F-F line crosses the metal region of the first device 1 and the metal region of the second device 2, and both ends of the F-F line are just located at the metal contact of the source region 12 of the first device 1 and the source of the second device 2 area 22 on the metal contact. As shown in FIG. 11 , the metal 11 of the first device 1 and the metal 21 of the second device 2 are separated by the metal spacing region 5 . Below the metal layer is an oxide layer 10 . There is no trench between the first source region 12 of the first device 1 and the second source region 22 of the second device 2 , but a certain distance is used so that current can no longer flow laterally. As shown, the first device 1 and the second device 2 collect respective currents via the source regions 12 and 22 respectively through the metal contacts 14 and 24 along the arrows I1 and I2 indicating the current flow directions. In this way, the current collection of the second device 2 will not affect the normal operation of the first device 1 .

Fig. 12 shows a sectional view along G-G in Fig. 10 . Referring back to FIG. 10 , the G-G line crosses the metal region of the second device 2 and its two ends are respectively located on the metal contacts 14 of the first source region 12 on both sides of the first device 1 . Referring to FIG. 12 , the metal 11 of the first device 1 and the metal 21 of the second device 2 are separated by a metal spacing region 5 . Below the metal layer is an oxide layer 10 . Since the source region metal contact 24 of the second device 2 is arranged at the position where G-G passes in the metal region of the second device 2, the second device 2 collects current along the arrow I2 representing the current flow, while the first device 1 collects the current through The first source region 12 on both sides of the G-G line collects current through the metal contact 14 , as shown by the arrow I1 indicating the flow direction of the current in the figure.

Fig. 13 shows a sectional view along H-H in Fig. 10 . Referring back to FIG. 10 , H-H completely falls on the area of the first device 1 and spans 3 trenches 13 , and the H-H line spans 2 source metal contacts 14 . Referring to FIG. 13 , the uppermost layer is the metal 11 of the first device 1 . Below the metal layer is an oxide layer 10. There are three trenches 13 in the body region below the oxide layer 10 . There is no source metal contact between the leftmost trench 13 and the middle trench. In addition, since the H-H line straddles the two source metal contacts 14, the two source metal contacts 14 are also correspondingly shown in this cross-sectional view. Through the two source metal contacts 14, the current between the corresponding trenches is collected along the arrow I1 indicating the current flow direction.

FIG. 14 shows a cross-sectional view at position 1001 in FIG. 10 . Referring back to FIG. 10 , the location 1001 falls on the area of the second device 2 , spans one trench 23 , and has one end on the source region metal contact 24 . Referring to FIG. 14 , the uppermost layer is the metal 21 of the second device 2 . In the middle part, since the source region 22 of the second device 2 spans 1 trench 23 , the trench 23 is shown here in the cross-sectional view. From the middle part to the right, the metal contact 24 is shown in the cross-sectional view because one end of the position 1001 is located on the source region metal contact 24, and the metal contact 24 collects the current along the arrow I2 indicating the current flow direction.

Likewise, it should be noted that, in the power device according to the embodiment of the present disclosure, the body regions of the second device 2 and the first device 1 except for the trenches are all active regions. That is to say, in addition to the second device 2 and the active region of the first device 1 itself, in the embedded part of the second device 2 and the first device 1 (including, for example, separating the source region of the second device 2 from the first device The part of the metal spacing region of the source region of 1, the source region part of the first device 1 under the metal of the second device 2 (the metal of the second device 2 on this part is the source lead-out line of the second device 2) ) has no additional high-concentration diffusion regions, ie, no desource regions. In this way, the embedding of the second device 2 is smooth and does not cause structural changes to the first device 1 , and therefore does not cause any adverse effects on the current and voltage performance of the first device 1 . In addition, since the embedded part of the second device 2 and the first device 1 has no de-source region, this part can still contribute to the current supply, so that no chip area is wasted.

The structure of the power device according to the present disclosure is described above through the embodiments. It is understood that the number of source regions and trenches may be the same or different than the described embodiments. It should also be noted that the structure of the second device is the same as that of the first device in the left half and the right half of the figure, the description about the left half is also applicable to the corresponding structure of the right half, and the description about the right half Also applies to the corresponding structure in the left half.

The present disclosure also provides a method for preparing a power device. FIG. 15 shows a method 1500 of fabricating a power device according to an example embodiment of the present invention. As shown in FIG. 15 , the method 1500 includes: S1501 , providing a substrate. Next, in step S1502, the body region of the first device and the body region of at least one second device are formed on the substrate. In step S1503, a plurality of first trenches are formed in the body region of the first device, and a plurality of second trenches are formed in the body region of the second device, wherein the second trenches of the second device and the first The corresponding first trenches of the devices are connected. Finally in step S1504, a plurality of first source regions for the first device and a plurality of second source regions for the second device are formed, wherein the plurality of first source regions are interconnected by the plurality of first trenches Electrically isolated, a plurality of second source regions are electrically isolated from each other through a plurality of second trenches, wherein the second source region of the second device is electrically isolated from the first source region of the first device through a metal spacer region, wherein the first Parts except the first trench and the second trench in the body regions of the first device and the second device are active regions.

In one implementation, multiple second source regions of the second device are arranged in a concentrated manner.

In one implementation, the substrate may be a P+N substrate, and the power device is an insulated gate bipolar transistor. In one implementation, the substrate may be an N+N substrate, and the power device is a metal oxide semiconductor field effect transistor.

In one implementation, each second source region of the second device corresponds to a corresponding one of the first source regions of the first device, and each second trench of the second device corresponds to a corresponding one of the first device's first source region. A groove communicates with each other. The method 1500 further includes forming a plurality of third trenches in the metal spacing region, each third trench corresponding to a second source region of the second device, and forming two corresponding to the second source region The second trenches are connected. The first trench, the second trench and the third trench are identical in structure. Alternatively, the first source region of the first device has a first metal contact region, the second source region of the second device has a second metal contact region, the boundary of the first metal contact region is separated from the boundary of the corresponding second metal contact region distance such that current can no longer flow laterally across the plane.

In one implementation, each second source region of the second device corresponds to two corresponding first source regions of the first device, and the method 1500 further includes forming a plurality of fourth trenches in the metal pitch region, each The fourth trench is three-terminal, corresponding to a second source region of the second device, and the two second trenches corresponding to the second source region and the two corresponding to the second source region The first trenches between the first source regions are connected. The first groove, the second groove, and the fourth groove are identical in structure.

As above, the power device and the manufacturing method thereof according to the present disclosure are discussed by means of specific embodiments. According to the technology of the present disclosure, the first device and the second device are simultaneously fabricated on the same substrate through the same process, wherein the first device and the second device are well electrically isolated. In addition, the first device and the second device are coupled and isolated in a unique manner, and since the part where the second device is embedded with the first device has no other high-concentration diffusion region (that is, no desource region), the second device's The embedding does not cause structural changes to the first device, and therefore does not cause any adverse effects on the current-voltage performance of the first device. In addition, the embedded part of the second device and the first device has no desource region, so this part can still contribute to the current supply, so that no chip area is wasted.

While at least one exemplary embodiment and method of preparation have been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or embodiments are by way of example only, and are not intended to limit the scope, application, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a road map for conveniently implementing the exemplary embodiment of the invention, and it is to be understood that various changes may be made in the function and arrangement of elements described in the exemplary embodiment. without departing from the scope of the invention as set forth in the appended claims and their legal equivalents.

Claims (16)

1. A power device, comprising: A first device having a plurality of first source regions and a plurality of first trenches, wherein the plurality of first trenches electrically isolates the plurality of first source regions from each other; at least one second device having a plurality of second source regions and a plurality of second trenches electrically isolating the plurality of second source regions from each other, wherein The second device is embedded in the first device, and the second groove of the second device communicates with the corresponding first groove of the first device, wherein the second the second source region of the device is electrically isolated from the first source region of the first device by a metal spacer region, and Wherein the body regions of the first device and the second device are all active regions except for the trenches, and the part of the second device embedded with the first device has no deactive region; The plurality of second source regions of the second device are concentratedly arranged; Each second source region of the second device corresponds to two corresponding first source regions of the first device, and the power device further includes a plurality of fourth trenches, each of the fourth trenches The groove has a three-terminal shape, corresponding to a second source region of the second device, and two second trenches corresponding to the second source region and two first trenches corresponding to the second source region The first trenches between the source regions are connected. 2. The power device according to claim 1, wherein the first device and the second device are formed on a P+N substrate, and the power device is an insulated gate bipolar transistor. 3. The power device of claim 1, wherein the first device and the second device are formed on an N+N substrate, and the power device is a Metal Oxide Semiconductor Field Effect Transistor. 4. The power device according to claim 1, wherein each second source region of the second device corresponds to a corresponding one of the first source regions of the first device, and each of the second device A second trench directly communicates with a corresponding first trench of the first device. 5. The power device according to claim 4, wherein the power device further comprises a plurality of third trenches, the third trenches are located in the metal spacing region, and each of the third trenches It corresponds to a second source region of the second device, and connects two second trenches corresponding to the second source region. 6. The power device according to claim 5, wherein the first trench, the second trench and the third trench are identical in structure. 7. The power device of claim 4, wherein the first source region of the first device has a first metal contact region, the second source region of the second device has a second metal contact region, the The border of the first metal contact region is at a distance from the border of the corresponding second metal contact region such that current can no longer flow laterally in the plane. 8. The power device of claim 1, wherein the first trench, the second trench, and the fourth trench are identical in structure. 9. A method for preparing a power device, comprising: provide the substrate; forming a body region of a first device and a body region of at least one second device on a substrate; A plurality of first trenches for the first device are formed in the body region of the first device, and a plurality of second trenches for the second device are formed in the body region of the second device. trenches, wherein the second trenches of the second device communicate with corresponding first trenches of the first device; forming a plurality of first source regions for the first device and a plurality of second source regions for the second device, wherein the plurality of first source regions pass through the plurality of first trenches are electrically isolated from each other, the plurality of second source regions are electrically isolated from each other by the plurality of second trenches, wherein the second source region of the second device and the first source region of the first device are electrically isolated by the metal spacer region, and Wherein the body regions of the first device and the second device are all active regions except for the trenches, and the part of the second device embedded with the first device has no deactive region; The plurality of second source regions of the second device are concentratedly arranged; Each second source region of the second device corresponds to respective two first source regions of the first device, and the method further includes forming a plurality of fourth trenches in the metal spacing region, Each of the fourth trenches is in a three-terminal shape, corresponding to a second source region of the second device, and connects the two second trenches corresponding to the second source region with the second source region The first trenches between the corresponding two first source regions in the region are connected. 10. The method for preparing a power device according to claim 9, wherein the first device and the second device are formed on a P+N substrate, and the power device is an insulated gate bipolar transistor . 11. The manufacturing method of a power device according to claim 9, wherein the first device and the second device are formed on an N+N substrate, and the power device is a metal oxide semiconductor field effect transistor. 12. The method for manufacturing a power device according to claim 9, wherein each second source region of the second device corresponds to a corresponding first source region of the first device, and the second Each second trench of a device is in direct communication with a corresponding one of the first trenches of said first device. 13. The method for manufacturing a power device according to claim 12, wherein the method further comprises forming a plurality of third trenches in the metal spacing region, each of the third trenches is connected to the second One second source region of the device corresponds to and communicates with two second grooves corresponding to the second source region. 14. The method for manufacturing a power device according to claim 13, wherein the first trench, the second trench and the third trench are identical in structure. 15. The method for fabricating a power device according to claim 12, wherein the first source region of the first device has a first metal contact region, and the second source region of the second device has a second metal contact region , the boundary of the first metal contact region is at a certain distance from the boundary of the corresponding second metal contact region, so that current can no longer flow laterally along the plane. 16. The method for preparing a power device according to claim 9, wherein the first groove, the second groove, and the fourth groove are identical in structure.