Semiconductor device including self-protecting current sensor

• US 10,249,612 B2
• Filed: 05/12/2015
• Issued: 04/02/2019
• Est. Priority Date: 05/14/2014
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Decker, Stefan, Illing, Robert, Nelhiebel, Michael
• Primary Examiner(s): Gordon, Matthew E.
• Application Number:
  US14/709,583
• Publication Number:
  US 20150333060A1
• Time in Patent Office: 1,421 Days
• CPC Class Codes: H01L 23/62 Protection against overvoltage, e.g. fuses, shunts
• CPC Class Codes: H01L 27/0266 using field effect transistors as protective elements
• CPC Class Codes: H01L 27/088 the components being field-effect transistors with insulated gate
• CPC Class Codes: H01L 29/0653 adjoining the input or output region of a field-effect device, e.g. the source or drain region
• CPC Class Codes: H01L 29/7827 Vertical transistors H01L29/7802, H01L29/78642 take precedence
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

A semiconductor device includes a semiconductor body having a first surface and a second surface opposite to the first surface. The semiconductor body includes a load current component having a load current transistor area and a sensor component including a sensor transistor area. The sensor transistor area has first and third transistor area parts differing from a second transistor area part between the first and third transistor area parts by a sensor transistor area element being absent in the second transistor area part. The second transistor area part is electrically disconnected from a parallel connection of the first and third transistor area parts by the sensor transistor area element being absent in the second transistor area part.

Claims

1. A semiconductor device comprising a semiconductor body having a first surface and a second surface opposite to the first surface, the semiconductor body comprising:

a load current component comprising a load current transistor area; and

a sensor component comprising a sensor transistor area,

wherein the sensor component is operable to supply a current proportional to a load current flowing through the load current component,

wherein the sensor transistor area is at least partly surrounded by the load current transistor area, or arranged at a boundary portion of one or more sides of the load current transistor area,

wherein the sensor transistor area comprises first and third transistor area parts differing from a second transistor area part between the first and the third transistor area parts by a sensor transistor area element being absent in the second transistor area part,

wherein the second transistor area part is electrically disconnected from a parallel connection of the first and the third transistor area parts by the sensor transistor area element being absent in the second transistor area part.

2. The semiconductor device of claim 1, wherein the sensor transistor area element is a source region of the sensor transistor area.

3. The semiconductor device of claim 1, wherein the sensor transistor area element is an electric contact structure on a source region of the sensor transistor area.

4. The semiconductor device of claim 1, wherein the first to third transistor area parts are arranged along a first lateral direction such that source regions of the first and the third transistor area parts are electrically coupled by a conductive line extended along the first direction.

5. The semiconductor device of claim 1, further comprising:

a first isolation layer on the first surface of the semiconductor body;

a first wiring layer on the first isolation layer, the first wiring layer comprising a load current contact structure electrically coupled to the load current transistor area and a sensor contact structure electrically coupled to the sensor transistor area;

a second isolation layer on the first wiring layer; and

a second wiring layer on the second isolation layer overlapping the load current transistor area and the sensor transistor area, the second wiring layer being electrically coupled to the load current contact structure and isolated from the sensor contact structure.

6. The semiconductor device of claim 5, wherein the load current contact structure and the sensor current contact structure comprise conductive lines extending in parallel.

7. The semiconductor device of claim 5, wherein the sensor transistor area element is a source region of the sensor transistor area at the first surface of the semiconductor body.

8. The semiconductor device of claim 5, wherein the sensor transistor area element is an electric contact structure electrically connecting the sensor contact structure with a source region of the sensor transistor area, the electric contact structure extending through the first isolation layer.

9. The semiconductor device of claim 1, wherein source regions of the sensor transistor area and source regions of the load current transistor area are at the first surface and a common drain region is at the second surface of the semiconductor body.

10. The semiconductor device of claim 9, wherein the load current component comprises a first trench and the sensor component comprises a second trench, the first and second trenches each comprising a gate electrode, the gate electrodes being electrically coupled with each other.