Semiconductor device

• US 10,490,628 B2
• Filed: 03/09/2018
• Issued: 11/26/2019
• Est. Priority Date: 11/15/2017
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Electronic Devices & Storage Corporation (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Okumura, Hideki
• Primary Examiner(s): Amer, Mounir S
• Application Number:
  US15/916,355
• Publication Number:
  US 20190148488A1
• Time in Patent Office: 627 Days
• CPC Class Codes: H01L 29/0615 by the doping profile or the shape or the arrangement of the PN junction, or with supplementary regions, e.g. junction termination extension [JTE] LDD or drain offset regions H01L29/7833
• 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
• 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 29/405 Resistive arrangements, e.g. resistive or semi-insulating field plates
• 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 29/66734 with a step of recessing the gate electrode, e.g. to form a trench gate electrode
• CPC Class Codes: H01L 29/7803 structurally associated with at least one other device assemblies H01L25/00; integrated circuits H01L27/00
• 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 29/7827 Vertical transistors H01L29/7802, H01L29/78642 take precedence

Abstract

A semiconductor device has a drain region of a first conductivity type; a first semiconductor region of the first conductivity type on the drain region; a MOSFET on an upper part of the first semiconductor region; a source electrode configured to cover the MOSFET; and a pair of electrical connection units on both sides of the first semiconductor region, the electrical connection units being configured to electrically connect the drain region and the source electrode while being electrically insulated from the first semiconductor region.

Claims

1. A semiconductor device, comprising:

a drain region of a first conductivity type;

a first semiconductor region of the first conductivity type on the drain region;

a MOSFET on an upper part of the first semiconductor region;

a source electrode configured to cover the MOSFET; and

a pair of electrical connection units on both sides of the first semiconductor region, the electrical connection units being configured to electrically connect the drain region and the source electrode while being electrically insulated from the first semiconductor region,

wherein each of the electrical connection units comprises;

a conductive film configured to electrically connect the drain region and the source electrode; and

a pair of first insulating films on both sides of the conductive film, the conductive film directly contacting the drain region.

2. The semiconductor device according to claim 1, wherein an electrical resistance of the conductive film is from 10⁷Ω

to 10¹⁰Ω

.

3. The semiconductor device according to claim 1, wherein the conductive film includes semi-insulating SiN or semi-insulating poly-crystalline silicon.

4. The semiconductor device according to claim 1, wherein each of the electrical connection units is filled with the conductive film between the pair of first insulating films.

5. The semiconductor device according to claim 1, wherein the pair of first insulating films extend into the drain region.

6. The semiconductor device according to claim 1, wherein an impurity concentration of the first conductivity type of the first semiconductor region is lower than an impurity concentration of the first conductivity type of the drain region.

7. The semiconductor device according to claim 1, wherein an electrical resistance between the source electrode and the drain region of the electrical connection units is from 10⁷Ω

to 10¹⁰Ω

.

8. The semiconductor device according to claim 1, wherein

the MOSFET comprises:

a second semiconductor region of a second conductivity type on the upper part of the first semiconductor region;

a source region of the first conductivity type on an upper part of the second semiconductor region; and

a gate region expending into the first semiconductor region through the source region and the second semiconductor region, the gate region being in contact with the source region, the first semiconductor region, and the second semiconductor region through a second insulating film.

9. A semiconductor device, comprising:

a drain region of a first conductivity type;

a first semiconductor region of the first conductivity type on the drain region;

a second semiconductor region of a second conductivity type on an upper part of the first semiconductor region;

a MOSFET in the first semiconductor region and the second semiconductor region;

a source electrode configured to cover the MOSFET;

a pair of electrical connection units formed on both sides of the first semiconductor region, the electrical connection units being configured to electrically connect the drain region and the source electrode while being electrically insulated from the first semiconductor region; and

a third semiconductor region of the second conductivity type, configured to extend toward the drain region from the second semiconductor region in the periphery of each of the electrical connection units and reach the drain region.

10. The semiconductor device according to claim 9, wherein the third semiconductor region connects the second semiconductor region and the drain region.

11. The semiconductor device according to claim 9, wherein

each of the electrical connection units comprises:

a conductive film configured to electrically connect the drain region and the source electrode; and

a pair of first insulating films on both sides of the conductive film.

12. The semiconductor device according to claim 11, wherein an electrical resistance of the conductive film is from 10⁷Ω

to 10¹⁰Ω

.

13. The semiconductor device according to claim 11, wherein the conductive film includes semi-insulating SiN or semi-insulating poly-crystalline silicon.

14. The semiconductor device according to claim 11, wherein each of the electrical connection units is filled with the conductive film between the pair of first insulating films.

15. The semiconductor device according to claim 11, wherein the pair of first insulating films extends into the drain region.

16. The semiconductor device according to claim 9, wherein an impurity concentration of the first conductivity type of the first semiconductor region is lower than an impurity concentration of the first conductivity type of the drain region.

17. The semiconductor device according to claim 9, an electrical resistance between the source electrode and the drain region of the electrical connection units is from 10⁷Ω

to 10¹⁰Ω

.

18. The semiconductor device according to claim 9, wherein

the MOSFET comprises:

the second semiconductor region of the second conductivity type on the upper part of the first semiconductor region;

a source region of the first conductivity type on an upper part of the second semiconductor region; and

a gate region penetrating into the first semiconductor region through the source region and the second semiconductor region, the gate region being in contact with the source region, the first semiconductor region, and the second semiconductor region through a second insulating film.