Semiconductor component having a semiconductor body with a cutout

• US 9,923,072 B2
• Filed: 06/03/2014
• Issued: 03/20/2018
• Est. Priority Date: 09/21/2010
• Status: Active Grant

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Inventors: Poelzl, Martin
• Primary Examiner(s): AU, BAC H
• Application Number:
  US14/294,548
• Publication Number:
  US 20140299933A1
• Time in Patent Office: 1,386 Days
• Field of Search: 257E29066, 257330, 257510, 257520, 257513, 257622, 438270, 438221, 438524, 438197, 438361, 438435, 438437
• CPC Class Codes: H01L 21/3086 characterised by the process involved to create the mask, e.g. lift-off masks, sidewalls, or to modify the mask, e.g. pre-treatment, post-treatment
• CPC Class Codes: H01L 21/31144 using masks
• CPC Class Codes: H01L 21/76286 Lateral isolation by refilling of trenches with polycristalline material
• CPC Class Codes: H01L 29/0847 of field-effect transistors with insulated gate H01L29/0653 takes precedence; with a passive supplementary region between source or drain and substrate related to punch-through, capacity or isolation phenomena H01L29/1079; with LDD or DDD structure H01L29/7833; for thin film transistors H01L29/78618
• CPC Class Codes: H01L 29/1095 Body region, i.e. base region, of DMOS transistors or IGBTs cell layout H01L29/0696
• CPC Class Codes: H01L 29/407 Recessed field plates, e.g. trench field plates, buried field plates
• CPC Class Codes: H01L 29/41741 for vertical or pseudo-vertical devices
• CPC Class Codes: H01L 29/41766 with at least part of the source or drain electrode having contact below the semiconductor surface, e.g. the source or drain electrode formed at least partially in a groove or with inclusions of conductor inside the semiconductor H01L29/41733 - H01L29/41758 take precedence
• CPC Class Codes: H01L 29/4236 within a trench, e.g. trench gate electrode, groove gate electrode
• CPC Class Codes: H01L 29/66681 Lateral DMOS transistors, i.e. LDMOS transistors
• CPC Class Codes: H01L 29/66727 with a step of recessing the source electrode
• CPC Class Codes: H01L 29/66734 with a step of recessing the gate electrode, e.g. to form a trench gate electrode
• CPC Class Codes: H01L 29/78 with field effect produced by an insulated gate H01L29/7725, H01L29/775, H01L29/778 take precedence
• CPC Class Codes: H01L 29/7813 with trench gate electrode, e.g. UMOS transistors trench gate electrodes per se H01L29/4236
• CPC Class Codes: H01L 29/78642 Vertical transistors

Abstract

A semiconductor component includes a semiconductor body having a surface and a cutout in the semiconductor body. The cutout extends from the surface of the semiconductor body into the semiconductor body in a direction perpendicular to the surface. The cutout has a base and at least one sidewall. The component further includes a layer on the surface of the semiconductor body and in the cutout. The layer forms a well above the cutout. The well has a well base, a well edge and at least one well sidewall. The at least one well sidewall forms an angle α in the range of 20° to 80° with respect to the surface of the semiconductor body. The layer has at least one edge which, proceeding from the well edge, extends in the direction of the surface of the semiconductor body.

Claims

1. A semiconductor component, comprising:

a semiconductor body having a top surface;

a gate trench cutout in the semiconductor body, the gate trench cutout extending from the top surface of the semiconductor body into the semiconductor body in a direction perpendicular to the top surface, and the gate trench cutout having a base and at least one sidewall;

a channel control electrode arranged in the gate trench cutout and isolated from the semiconductor body by a gate dielectric;

a layer formed over and covering a portion of the top surface and arranged in the gate trench cutout above the channel control electrode, the layer forming a well above the gate trench cutout, the well having a well base, a well edge and at least one well sidewall, the at least one well sidewall forming an angle α

in the range of 20°

to 80°

with respect to the top surface of the semiconductor body; and

wherein the layer has at least one edge which, proceeding from the well edge, extends in the direction of the top surface of the semiconductor body.

2. A semiconductor component according to claim 1, wherein the layer covers the top surface of the semiconductor body proceeding from the sidewall of the cutout over a distance of 50 nm to 150 nm.

3. A semiconductor component according to claim 1, further comprising a trench formed in the semiconductor body, the trench having at least one trench sidewall which, proceeding from the at least one edge of the layer, extends into the semiconductor body.

4. A semiconductor component according to claim 1, wherein the angle α

is in the range of 40°

to 45°

with respect to the top surface of the semiconductor body.

5. A semiconductor component according to claim 1, further comprising a channel zone formed in the semiconductor body and isolated from the channel control electrode by the gate dielectric.

6. A semiconductor component according to claim 5, further comprising a source zone formed in the semiconductor body above the channel zone and isolated from the channel control electrode by the gate dielectric.

7. A semiconductor component according to claim 6, further comprising:

a trench formed in the semiconductor body, the trench having at least one trench sidewall which, proceeding from the at least one edge of the layer, extends into the semiconductor body; and

a common connection electrode for the source zone and the channel zone arranged in the trench.

8. A semiconductor component according to claim 1, further comprising a field electrode formed in the gate trench cutout below the channel control electrode, the field electrode being isolated from the semiconductor body by a field dielectric.