TWI422036B - High voltage device and manufacturing method thereof - Google Patents

Description

High voltage component and method of manufacturing same

The present invention relates to a high voltage component and a method of fabricating the same, and more particularly to a high voltage component utilizing a deep trench isolation structure between a source and a drain to increase a breakdown voltage and a method of fabricating the same.

Fig. 1 shows a cross-sectional view of a high voltage element, which is structured as follows. The insulating structure 12 is formed in the P-type substrate 11 to define a first element region 100 and a second element region 200, and the insulating structure 12 is, for example, a local oxidation of silicon (LOCOS) structure. On the P-type substrate 11, a gate 13 is formed; in the first element region 100, an N-type source 14, a P-type body 16 and a P-type body region 17 are formed; and in the second device region 200, a N is formed. The type drain 15; between the source 14 and the drain 15, forms an N-type well region 18. When the component is in operation, it is often coupled to a high voltage of tens to hundreds of volts. In order to increase the high voltage that the high voltage component can withstand, to increase the application range of the high voltage component, it is necessary to reduce the high voltage in the high voltage component. The high electric field to increase the breakdown voltage of the component.

In view of the above, the present invention is directed to the above-mentioned deficiencies of the prior art, and provides a high voltage component and a manufacturing method thereof, which can reduce a high electric field caused by a high voltage inside the component, or increase a breakdown voltage of the component operation to increase the high voltage component. Application range.

It is an object of the present invention to provide a high voltage component and a method of manufacturing the same.

To achieve the above object, the present invention provides a high voltage component comprising: a first conductivity type substrate having an insulating structure to define an element region; a gate formed on the first conductivity type substrate; a source and a drain electrode formed in the element region, having a second conductivity type impurity doped, respectively formed on both sides of the gate; a second conductivity type well region formed in the first conductive type substrate, from a top view </ RTI> the first deep trench isolation structure is formed in the first conductive type substrate, and the first deep trench isolation structure is located in the first conductive type substrate The second conductive type well region is located between the drain and the source, and is deeper than the second conductive type well region by a cross-sectional view.

In another aspect, the present invention also provides a method for manufacturing a high voltage device, comprising: forming an insulating structure on a first conductive type substrate to define an element region; forming a gate on the first conductive type substrate; respectively forming a source and a drain are disposed in the component region and disposed on both sides of the gate, the source and the drain have a second conductivity type impurity doping; forming a second conductivity type well region in the first conductivity type In the substrate, viewed from a top view, the drain is located in the second conductive type well region; and at least one first deep trench insulating structure is formed in the first conductive type substrate, which is viewed from a top view, the first deep trench The insulating structure is located in the second conductive type well region and is located between the drain and the source, and is deeper than the second conductive type well region by a cross-sectional view.

The high voltage component may further include a first peripheral region having a first conductivity type impurity doping. The first peripheral region completely or partially surrounds the first deep trench isolation structure from a top view, which is viewed from a cross-sectional view. Less than the second conductivity type well region.

The high voltage component may further comprise a body region, which is covered by a top view and a cross-sectional view, the body region covering the source.

The high voltage component is viewed from a cross-sectional view, wherein the insulating structure partially overlaps the gate, and a portion of the insulating structure is located below the gate.

The high voltage component may further comprise a second deep trench isolation structure formed on a periphery of the component region, and the component region is defined together with the insulating structure.

The high voltage component may further comprise a second peripheral region having a second conductivity type impurity doping, wherein the second peripheral region completely or partially surrounds the first peripheral region, as viewed from a cross-sectional view, the depth is less than The second conductive type well region.

The purpose, technical content, features and effects achieved by the present invention will be more readily understood by the detailed description of the embodiments.

The drawings in the present invention are schematic and are mainly intended to represent the process steps and the relationship between the layers, and the shapes, thicknesses, and widths are not drawn to scale.

Referring to Figures 2A and 2B, a first embodiment of the present invention is shown. Fig. 2A shows a top view of the present embodiment; please also refer to Fig. 2B, showing a cross-sectional view taken along line AA' in Fig. 2A. First, a first conductive type substrate 11 having an insulating structure 12 to define the element regions 100 and 200 is provided. Next, a gate 13 is formed on the first conductive substrate 11. Then, in the first element region 100, the second conductive type source 14, the first conductive type body electrode 16, and the first conductive type body region 17 are formed. In the second element region 200, a second conductivity type drain 15 is formed. Between the source 14 and the drain 15, a second conductivity type well region 18 is formed. In the substrate 11, a first deep trench isolation structure 19 is formed. The second deep trench isolation structure 19 is located in the second conductive well region 18 and is located between the drain 14 and the source 15 as viewed from a second view of FIG. As seen in section 2B of the cross-sectional view, the first deep trench isolation structure 19 is deeper than the second conductivity type well region 18. Herein, the insulating structure 12 partially overlaps the gate 13 and the partial insulating structure 12 is located below the 13 gate, as viewed in section 2B of the cross-sectional view. The body region 17 encloses the source 14 from the second view of the top view and the second view of the cross-sectional view.

Please refer to Figures 2C and 2D to explain how the first embodiment reduces the internal electric field of the component. As shown in FIG. 2C, in the PN junction, for example, in the N-type region, the first deep trench isolation structure 19 is formed, and the first deep trench isolation structure 19 is deeper than the N-type region. In a preferred embodiment, the plurality of first deep trench isolation structures 19 are arranged perpendicular to the direction of the electric field and at an appropriate distance, but this is only preferred but not absolutely necessary, that is, the first deep trench isolation structures 19 do not have to be aligned into one column. And the distance between them does not have to be equidistant. Please refer to Figure 2D for the relationship between electric field and position in the PN junction. As shown, the electric field versus position curve of the first deep trench isolation structure 19 is not shown, as shown by the dashed line in the figure, and there is a relative maximum value of the electric field near the PN junction. The solid line in the figure shows the electric field versus position curve of the first deep trench isolation structure 19. The electric field versus position curve having the first deep trench isolation structure 19 significantly reduces the electric field near the PN junction relative to the electric field versus position curve in which the first deep trench isolation structure 19 is not disposed.

Figures 3A-3D show a second embodiment showing the invention. Fig. 3A is a top view showing the embodiment; and Fig. 3B-3D is a cross-sectional view showing the manufacturing flow of the BB' line in Fig. 3A of the present embodiment. Referring to FIG. 3A, it is shown that the present embodiment is different from the first embodiment in that a first peripheral region 20 doped with a first conductivity type impurity is formed on the periphery of the first deep trench insulating structure 19. As seen from the top view 3A, the first peripheral region 20 may completely surround the first deep trench isolation structure 19 (as shown) or only partially surround the first deep trench isolation structure 19 (in the latter case, for example, the first peripheral region 20) The upper side, the lower side, or the upper and lower sides of the first deep trench isolation structure 19 may be surrounded only; the first peripheral region 20 is deeper than the second conductive well region 18 as viewed from a 3D view of the cross-sectional view.

Please refer to the schematic diagram of the manufacturing process in Figure 3B-3D. First, a substrate 11 having a first conductivity type, such as, but not limited to, a P-type substrate, is provided, and a first peripheral region 20 and a first deep trench isolation structure 19 are formed therein. Next, as shown in FIG. 3C, the insulating structure 12 is formed to define the first element region 100 and the second element region 200, and the second conductive type well region 18; wherein the insulating structure 12 can be, for example, as shown in FIG. 3B. The LOCOS structure shown may also be a shallow trench isolation (STI) structure.

Next, please continue to refer to FIG. 3D to form the gate 13 on the substrate 11. Then, by the lithography technique and the mask of the gate 13 and the ion implantation technique, the first conductivity type impurity, such as but not limited to a P type impurity, is implanted into the defined region in the form of accelerated ions. To form the body region 17 and the body pole 16.

Next, by lithography and the mask of the gate 13, and by ion implantation technology, the second conductivity type impurities, such as but not limited to N-type impurities, are implanted in the form of accelerated ions. Within the region, a source 14 and a drain 16 are formed.

Figure 4 shows a third embodiment of the present invention. Unlike the first embodiment, this embodiment applies the present invention to another high voltage device, such as the lateral double diffused metal oxide semiconductor shown in Fig. 4. (lateral double diffused metal oxide semiconductor, LDMOS) component. Unlike the first embodiment, this embodiment shows that the present invention can be applied to an LDMOS device having no body region 17.

Figure 5 shows a fourth embodiment of the present invention, which is similar to the third embodiment, but which is applied to another high voltage component, that is, a double diffused drain metal oxide semiconductor. Schematic diagram of semiconductor, DDDMOS). Different from the third embodiment, this embodiment shows that the present invention can be applied to a DDDMOS device in which the gate 13 and the insulating structure do not overlap each other. The insulating structure 12 may be, for example, a LOCOS structure as shown in FIG. 5 or an STI structure.

6A and 6B show a fifth embodiment of the present invention, and Fig. 6A shows a top view of the present embodiment; and Fig. 6B shows a cross-sectional view of the CC' line of the present embodiment in Fig. 6A. Different from the first embodiment, in the high-voltage component, as seen from the top view 6A, the first peripheral region 20 is located only on the upper and lower sides of the first deep trench isolation structure 19, rather than completely surrounding the first deep trench. Insulation structure 19. It can be seen that the first peripheral region 20 can also be designed in various shapes, and is not limited to the rectangular shape shown in each embodiment.

7A and 7B, showing a sixth embodiment of the present invention, FIG. 7A shows a top view of the embodiment; and FIG. 7B shows a DD' line of the present embodiment in FIG. 7A. A schematic cross-sectional view. Unlike the second embodiment, the gate 13 of the high voltage element has a ring structure. In addition, the present embodiment is intended to illustrate that some of the high voltage elements have a second deep trench isolation structure 21 formed on the periphery of the element regions 100 and 200, together with the insulating structure 12 defining the element regions 100 and 200, and the present invention is applicable to such In the high voltage component having the second deep trench insulation structure 21. In the process, the first deep trench isolation structure 19 can be formed using the same process steps as the second deep trench isolation structure 21 without the need for additional steps.

8A and 8B show a seventh embodiment of the present invention. Unlike the second embodiment, the high voltage device further includes a second peripheral region 21 having a second conductivity type impurity doping, which is viewed from the top view. As a matter of view, the second peripheral region 21 may completely surround the first peripheral region 20 (as shown) or may only partially surround the first peripheral region 20 (eg, surrounding its upper side, lower side, or upper and lower sides). As seen in section 8B of the cross-sectional view, the second peripheral region 21 is deeper than the second conductive well region 18.

The present invention has been described with reference to the preferred embodiments thereof, and the present invention is not intended to limit the scope of the present invention. In the same spirit of the invention, various equivalent changes can be conceived by those skilled in the art. For example, other process steps or structures, such as deep well areas, may be added without affecting the main characteristics of the components; for example, lithography is not limited to reticle technology, and may also include electron beam lithography; The invention can also be applied to a symmetrical high-voltage component, as long as the other regions, such as the second conductive well region 18, are disposed oppositely, and the first deep trench isolation structure 19, the first peripheral region 20, For example, in the flow of the high-voltage component manufacturing method described in the embodiments, the order of the steps may be changed or interchanged, as long as the relative relationship and the thermal budget are considered. The above and other equivalent variations are intended to be covered by the scope of the invention.

11. . . Substrate

12. . . Insulation structure

13. . . Gate

14. . . Source

15. . . Bungee

16. . . Body pole

17. . . Body area

18. . . Second conductivity type well area

19. . . First deep trench insulation structure

20. . . First peripheral area

twenty one. . . Second deep trench insulation structure

twenty two. . . Second peripheral zone

100,200. . . Component area

Figure 1 shows a cross-sectional view of a high voltage component.

Figures 2A and 2B show a first embodiment of the present invention.

The 2C and 2D diagrams explain how the first embodiment reduces the internal electric field of the component.

Figures 3A-3D show a second embodiment showing the invention.

Fig. 4 shows a third embodiment of the present invention.

Fig. 5 shows a fourth embodiment of the present invention.

Figures 6A and 6B show a fifth embodiment of the present invention.

Figures 7A and 7B show a sixth embodiment of the present invention.

Figures 8A and 8B show a seventh embodiment of the present invention

11. . . Substrate

12. . . Insulation structure

13. . . Gate

14. . . Source

15. . . Bungee

16. . . Body pole

17. . . Body area

18. . . Second conductivity type well area

19. . . First deep trench insulation structure

Claims (10)

A high voltage component comprising: a first conductivity type substrate having an insulating structure to define an element region; a gate formed on the first conductivity type substrate; a source and a drain formed in the component region Doping with a second conductivity type impurity, respectively formed on both sides of the gate; a second conductivity type well region formed in the first conductivity type substrate, viewed from a top view, the drain is located at the second In the conductive well region, at least one first deep trench insulation structure is formed in the first conductive type substrate, and the first deep trench isolation structure is located in the second conductive type well region and located at the top view Between the pole and the source, viewed from a cross-sectional view, the depth is greater than the second conductive type well region; and a first peripheral region having a first conductivity type impurity doping, which is viewed from a top view, the first peripheral region The first deep trench insulation structure is completely surrounded, and the depth is smaller than that of the second conductive type well region. The high voltage component according to claim 1, further comprising a body region, wherein the body region covers the source from a top view and a cross-sectional view. The high voltage component of claim 1, wherein the insulating structure partially overlaps the gate and a portion of the insulating structure is located below the gate. The high voltage component of claim 1, further comprising a second deep trench isolation structure formed on a periphery of the component region, the component region being defined together with the insulating structure. The high voltage component of claim 1, further comprising a second peripheral region having a second conductivity type impurity doping, wherein the second peripheral region completely or partially surrounds the first peripheral region , as seen from the cross-sectional view, its depth is less than The second conductive type well region. A method for manufacturing a high voltage component, comprising: forming an insulating structure on a first conductive type substrate to define an element region; forming a gate on the first conductive type substrate; forming a source and a drain respectively for the component The region is disposed on both sides of the gate, the source and the drain have a second conductivity type impurity doping; forming a second conductivity type well region in the first conductive type substrate, which is viewed from a top view, The drain is located in the second conductive type well region; forming at least one first deep trench insulating structure in the first conductive type substrate, wherein the first deep trench insulating structure is located in the second conductive type well region And between the drain and the source, viewed from a cross-sectional view, the depth is greater than the second conductive type well region; and forming a first peripheral region having a first conductivity type impurity doping, viewed from a top view The first peripheral region completely surrounds the first deep trench isolation structure, and the depth is smaller than the second conductive type well region by a cross-sectional view. The method for manufacturing a high voltage component according to claim 6, further comprising forming a body region, wherein the body region covers the source from a top view and a cross-sectional view. The method for manufacturing a high voltage component according to claim 6, wherein the insulating structure partially overlaps the gate and a portion of the insulating structure is located below the gate. The method for manufacturing a high voltage component according to claim 6, further comprising forming a second deep trench insulating structure on a periphery of the component region, and defining the component region together with the insulating structure. The method for manufacturing a high voltage component according to claim 6, further comprising forming a second peripheral region having a second conductivity type impurity doping, wherein the second peripheral region completely or partially surrounds the first region a peripheral area, viewed from a cross-sectional view The depth is smaller than the second conductive type well region.