Multi-directional trenching of a die in manufacturing superjunction devices

• US 9,543,380 B2
• Filed: 06/27/2011
• Issued: 01/10/2017
• Est. Priority Date: 09/28/2007
• Status: Active Grant

• Current Assignee: IceMOS Technology Ltd
• Original Assignee: Michael Wayne Shore
• Inventors: Ishiguro, Takeshi, Sugiura, Kenji, Griffin, Hugh J.
• Primary Examiner(s): NGUYEN, CUONG QUANG
• Application Number:
  US13/169,378
• Publication Number:
  US 20110254137A1
• Time in Patent Office: 2,024 Days
• Field of Search: 257621-628
• US Class Current: 1/1
• CPC Class Codes: H01L 29/0634 Multiple reduced surface field (multi-RESURF) structures, e.g. double RESURF, charge compensation, cool, superjunction (SJ), 3D-RESURF, composite buffer (CB) structures

Abstract

A method of manufacturing a superjunction device includes providing a semiconductor wafer having at least one die. At least one first trench having a first orientation is formed in the at least one die. At least one second trench having a second orientation that is different from the first orientation is formed in the at least one die.

Claims

1. A superjunction device comprising:

(a) a semiconductor wafer, the semiconductor wafer including at least one die;

(b) at least one first trench formed in the at least one die, the at least one first trench having a first orientation and defining a first area; and

(c) at least one second trench formed in the at least one die, the at least one second trench having a second orientation that is different from the first orientation, the at least one second trench defining a second area such that a ratio of the first area to the second area is about one-to-one.

2. The device of claim 1, further comprising:

(d) at least one additional trench formed in the at least one die, the at least one additional trench having an orientation that is different from at least one of the first orientation and the second orientation.

3. A superjunction device comprising:

(a) a semiconductor wafer, the semiconductor wafer including at least one die;

(b) a first plurality of trenches in the at least one die, each of the first plurality of trenches having a first orientation, the first plurality of trenches defining a first area; and

(c) a second plurality of trenches in the at least one die, each of the second plurality of trenches having a second orientation that is different from the first orientation, the second plurality of trenches defining a second area such that a ratio of the first area to the second area is about one-to-one.

4. The device of claim 3, wherein

(i) each of the first plurality of trenches has a length dimension, the length dimension of each of the first plurality of trenches being different from at least one other of the first plurality of trenches;

and

(ii) each of the second plurality of trenches has a length dimension, the length dimension of each of the second plurality of trenches being different from at least one other of the second plurality of trenches.

5. The device of claim 3, wherein

(i) each of the first plurality of trenches has a length dimension, the length dimension of each of the first plurality of trenches being identical;

and

(ii) each of the second plurality of trenches has a length dimension, the length dimension of each of the second plurality of trenches being identical.