Semiconductor component and method for producing a semiconductor component

• US 8,269,282 B2
• Filed: 12/15/2010
• Issued: 09/18/2012
• Est. Priority Date: 12/22/2009
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Zelsacher, Rudolf, Zundel, Markus, Wood, Andrew
• Primary Examiner(s): Lee, Eugene
• Application Number:
  US12/968,978
• Publication Number:
  US 20110147843A1
• Time in Patent Office: 643 Days
• Field of Search: 257/367, 257330-334, 257/E29.009
• US Class Current: 257/367
• CPC Class Codes: H01L 29/0865 Disposition
• CPC Class Codes: H01L 29/0869 Shape cell layout H01L29/0696
• CPC Class Codes: H01L 29/0878 Impurity concentration or distribution
• CPC Class Codes: H01L 29/0882 Disposition
• CPC Class Codes: H01L 29/0886 Shape
• CPC Class Codes: H01L 29/407 Recessed field plates, e.g. trench field plates, buried field plates
• CPC Class Codes: H01L 29/4236 within a trench, e.g. trench gate electrode, groove gate electrode
• CPC Class Codes: H01L 29/42368 the thickness being non-uniform
• CPC Class Codes: H01L 29/66719 With a step of forming an insulating sidewall spacer
• 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 29/7813 with trench gate electrode, e.g. UMOS transistors trench gate electrodes per se H01L29/4236

Abstract

A semiconductor component includes at least one field effect transistor disposed along a trench in a semiconductor region and has at least one locally delimited dopant region in the semiconductor region. The at least one locally delimited dopant region extends from or over a pn junction between the source region and the body region of the transistor or between the drain region and the body region of the transistor into the body region as far as the gate electrode, such that a gap between the pn junction and the gate electrode in the body region is bridged by the locally delimited dopant region.

Claims

1. A semiconductor component, comprising:

at least one field effect transistor disposed along a trench extending vertically downward from a horizontal top surface in a semiconductor region, the at least one field effect transistor having a source region of a first conductivity type along the trench and extending downward from the horizontal top surface, a drain region of the first conductivity type, and a body region of a second conductivity type disposed between the source region and the drain region in the semiconductor region so as to form a first generally horizontal junction between the source region and the body region and a second generally horizontal junction between the body region and the drain region, the first and second generally horizontal junctions having a first vertical depth and a second vertical depth, respectively, relative to the horizontal top surface;

a gate electrode in the trench along the body region, said gate electrode being arranged in a manner isolated from the body region by a gate dielectric and extending vertically from an uppermost surface of the gate electrode, at a third vertical depth relative to the horizontal top surface, to a lower-most surface of the gate electrode, at a fourth vertical depth relative to the horizontal top surface, such that either the third vertical depth is greater than the first vertical depth or the fourth vertical depth is less than the second vertical, or both; and

a first locally delimited dopant region of the first conductivity type in the semiconductor region, the first locally delimited dopant region extending either downward from the first generally horizontal junction between the source region and the body region to below the third vertical depth, or extending upward from the second generally horizontal junction between the drain region and the body region to above the fourth depth, so that a part of the first dopant region extends vertically in the body region to bridge a gap in the body region between the first vertical depth and the third vertical depth or a gap in the body region between the second vertical depth and the fourth vertical depth.

2. The semiconductor component according to claim 1, wherein the trench comprises a wide upper trench region and a narrower lower trench region such that a step is formed in the semiconductor region.

3. The semiconductor component according to claim 1, wherein the gate dielectric and the gate electrode are arranged in a first region of the trench and a field plate is arranged in a second region of the trench along the drain region, and the field plate is isolated from the drain region by a field plate dielectric.

4. The semiconductor component according to claim 3, wherein the gate electrode is isolated from the field plate by a dielectric.

5. The semiconductor component of claim 1, wherein the first locally delimited dopant region extends downward from the first generally horizontal junction between the source region and the body region to below the third vertical depth, so as to bridge a first gap in the body region between the first vertical depth and the third vertical depth, the semiconductor component further comprising a second locally delimited dopant region extending upward from the second generally horizontal junction between the drain region and the body region to above the fourth depth, so that a part of the first dopant region extends vertically in the body region to bridge a second gap in the body region between the second vertical depth and the fourth vertical depth.