Power semiconductor device of stripe cell geometry

• US 9,583,560 B2
• Filed: 03/04/2015
• Issued: 02/28/2017
• Est. Priority Date: 05/20/2014
• Status: Active Grant

• Current Assignee: uPI Semiconductor Corporation (ASUSTek Computer, Inc.)
• Original Assignee: UBIQ Semiconductor Corp. (ASUSTek Computer, Inc.)
• Inventors: Tu, Kao-Way, Tsai, Yi-Yun, Chang, Yuan-Shun
• Primary Examiner(s): Jackson, Jr., Jerome
• Assistant Examiner(s): Lin, John
• Application Number:
  US14/637,457
• Publication Number:
  US 20150340433A1
• Time in Patent Office: 727 Days
• Field of Search: 257/409
• US Class Current: 1/1
• CPC Class Codes: H01L 27/088 the components being field-effect transistors with insulated gate
• CPC Class Codes: H01L 29/0619 with a supplementary region doped oppositely to or in rectifying contact with the semiconductor containing or contacting region, e.g. guard rings with PN or Schottky junction
• CPC Class Codes: H01L 29/0692 Surface layout
• CPC Class Codes: H01L 29/0696 of cellular field-effect devices, e.g. multicellular DMOS transistors or IGBTs
• CPC Class Codes: H01L 29/404 Multiple field plate structures
• CPC Class Codes: H01L 29/4238 characterised by the surface lay-out
• CPC Class Codes: H01L 29/7811 with an edge termination structure guard regions per se H01L29/0619; field plates per se H01L29/402
• CPC Class Codes: H01L 29/7813 with trench gate electrode, e.g. UMOS transistors trench gate electrodes per se H01L29/4236

Abstract

A power semiconductor device of stripe cell geometry including a substrate, a plurality of striped power semiconductor units, and a guard ring structure is provided. The substrate has an active area and a termination area surrounding the active area defined thereon. The striped semiconductor unit includes a striped gate conductive structure. The striped semiconductor units are located in the active area. The guard ring structure is located in the termination area and includes at least a ring-shaped conductive structure surrounding the striped power semiconductor units. The ring-shaped conductive structure and the striped gate conductive structures are formed on the same conductive layer, and at least one of the striped gate conductive structures is separated from the nearby ring-shaped conductive structure and electrically connected to the nearby ring-shaped conductive structure through the gate metal pad.

Claims

1. A power semiconductor device of stripe cell geometry, comprising:

a substrate, the substrate having an active area and a termination area surrounding the active area defined thereon;

a plurality of striped power semiconductor units, the striped power semiconductor units being located in the active area, each of the striped power semiconductor units comprising a striped gate conductive structure; and

a guard ring structure, the guard ring structure being located in the termination area and comprising at least a ring-shaped conductive structure surrounding the striped power semiconductor units,

wherein a body-doped region is defined in the active area through the striped gate conductive structure and a doped region is defined in the termination area through the ring-shaped conductive structure, and there is a fixed distance between the body-doped region and the doped region, at least one of the striped gate conductive structures is separated from the ring-shaped conductive structure innermost of the termination area, a gate metal pad is located above the ring-shaped conductive structures and electrically connected to at least two of the ring-shaped conductive structures.

2. The power semiconductor device of stripe cell geometry of claim 1, wherein the ring-shaped conductive structure and the striped gate conductive structures are located in the same conductive layer.

3. The power semiconductor device of stripe cell geometry of claim 1, wherein the striped gate conductive structure is electrically connected to the ring-shaped conductive structure innermost of the termination area through a gate metal pad.

4. The power semiconductor device of stripe cell geometry of claim 3, wherein the gate metal pad is located at a side of the termination area and the gate metal pad extends to cover an end of the striped gate conductive structure, and a long side of the gate metal pad is vertical to an alignment of the striped gate conductive structures.

5. The power semiconductor device of stripe cell geometry of claim 3, wherein the gate metal pad extends into the active area from a center of a side of the termination area, and an extending direction of the gate metal pad is vertical to an alignment of the striped gate conductive structures.

6. The power semiconductor device of stripe cell geometry of claim 1, wherein the ring-shaped conductive structure is a ring-shaped poly-silicon structure and the striped gate conductive structure is a striped gate poly-silicon structure.

7. The power semiconductor device of stripe cell geometry of claim 1, further comprising two gate metal pads corresponding to two opposite sides of the termination area.

8. The power semiconductor device of stripe cell geometry of claim 1, wherein the striped gate conductive structure and the ring-shaped conductive structure are covered by an inter-level dielectric layer, the inter-level dielectric layer has a plurality of contact windows corresponding to the striped gate conductive structure and the ring-shaped conductive structure respectively, a gate metal pad is electrically connected to the striped gate conductive structure and the ring-shaped conductive structure through the contact windows.

9. The power semiconductor device of stripe cell geometry of claim 1, wherein the ring-shaped conductive structures define a plurality of ring-shaped doped regions in the termination area, each ring-shaped conductive structure comprises a first section and a second section, the second section is wider than the first section, the ring-shaped doped regions formed at two sides of the first section are separated to each other and the ring-shaped doped regions formed at two sides of the second section are connected to each other.

10. The power semiconductor device of stripe cell geometry of claim 9, wherein each ring-shaped conductive structure further comprises a third section, the third section is located at center of the second section and electrically connected to the gate metal pad, and the third section is wider than the second section.