Isolated hall sensor structure

Patent metadata

Field	Value
Publication number	US-11486944-B2
Application number	US-202016897851-A
Country	US
Kind code	B2
Filing date	Jun 10, 2020
Priority date	Jun 11, 2019
Publication date	Nov 1, 2022
Grant date	Nov 1, 2022

Abstract

An isolating Hall sensor structure having a support structure made of a substrate layer and an oxide layer, a semiconductor region of a first conductivity type which is integrally connected to a top side of the oxide layer, at least one trench extending from the top side of the semiconductor region to the oxide layer of the support structure, at least three first semiconductor contact regions of the first conductivity type, each extending from a top side of the semiconductor region into the semiconductor region. The at least one trench surrounds a box region of the semiconductor region. The first semiconductor contact regions are each arranged in the box region of the semiconductor region and are each spaced apart from one another. A metallic connection contact layer is arranged on each first semiconductor contact region.

First claim

What is claimed is:

1. An isolating Hall sensor structure comprising:
a support structure formed of a substrate layer and an oxide layer;
a semiconductor region of a first conductivity type that is integrally connected to a top side of the oxide layer;
a plurality of trenches each extending from the top side of the semiconductor region to the oxide layer of the support structure, the plurality of trenches surrounding a box region (active region) of the semiconductor region;
a dielectric isolation layer formed on side of each of the plurality of trenches;
at least three first semiconductor contact regions of the first conductivity type, each extending from a top side of the semiconductor region into the semiconductor region, the first semiconductor contact regions being arranged in the box region of the semiconductor region and are spaced apart from one another;
a first metallic connection contact layer arranged on each the first semiconductor contact regions;
at least one second semiconductor contact region of a second conductivity type that extends in the box region from the top side of the semiconductor region into the semiconductor region, each second semiconductor contact region extending at least partially along the trench and is spaced from the first semiconductor contact regions; and
a second metallic connection contact layer arranged on each second semiconductor contact region,
wherein at least regions of the semiconductor region that extend between the first semiconductor contact regions or an entirety of the semiconductor region are free of threshold voltage implantation.

2. The Hall sensor structure according to claim 1 , wherein the at least three first semiconductor contact regions have a layer thickness of 0.1 μm-4 μm.

3. The Hall sensor structure according to claim 1 , wherein the Hall sensor structure has exactly one second semiconductor contact region and the second semiconductor contact region has a closed form extending along a perimeter of the box region of the semiconductor region.

4. The Hall sensor structure according to claim 1 , wherein all second semiconductor contact regions contained in the Hall sensor structure extend along at least 50% or at least 75% or at least 95% of a perimeter of the box region of the semiconductor region.

5. The Hall sensor structure according to claim 1 , wherein the box region of the semiconductor region has a rectangular top side, and
wherein the at least one second semiconductor contact region extends along a first edge and/or along a second edge and/or along a third edge and/or along a fourth edge of the rectangular top side.

6. The Hall sensor structure according to claim 1 , wherein each second semiconductor contact region adjoins the trench or has a distance of at most 10 nm or at most 100 nm from the trench.

7. The Hall sensor structure according to claim 1 , wherein each of the plurality of trenches is filled with a polysilicon.

8. The Hall sensor structure according to claim 1 , wherein side walls of the plurality of trenches are formed by the semiconductor region and are coated with a second dielectric isolation layer, and
wherein the second dielectric isolation layer has a thickness between 3 nm and 30 nm.

9. The Hall sensor structure according to claim 1 , wherein the first conductivity type is n-type and the second conductivity type is p-type or wherein the first conductivity type is p-type and the second conductivity type is n-type.

10. The Hall sensor structure according to claim 1 , wherein the first semiconductor contact regions each have a dopant concentration of 5·10 18 N/cm 3 .

11. The Hall sensor structure according to claim 1 , wherein the semiconductor region has a dopant concentration of 5·10 14 -5·10 17 N/cm 3 .

12. The Hall sensor structure according to claim 1 , wherein the first semiconductor contact regions are each spaced apart from the trench.

13. The Hall sensor according to claim 1 , wherein the at least three first semiconductor contact regions are formed on a top surface of the semiconductor region.

14. The Hall sensor according to claim 1 , wherein the at least three first semiconductor contact regions each have a first metallic connection contact layer formed thereon.

15. The Hall sensor according to claim 1 , further comprising a third dielectric isolation layer formed on a top surface of the semiconductor region between the at least three first semiconductor contact regions.

16. The Hall sensor according to claim 1 , wherein the plurality of trenches comprises exactly two trenches.

17. The Hall sensor according to claim 1 , wherein the substrate is a silicon-on-insulator (SOI) semiconductor wafer.

18. The Hall sensor according to claim 1 , wherein the oxide layer forms a bottom of the plurality of trenches.

19. An isolating Hall sensor structure comprising:
a substrate layer;
an oxide layer disposed on the substrate layer;
a semiconductor region of a first conductivity type connected to a top side of the oxide layer;
a plurality of trenches each extending from the top side of the semiconductor region to the oxide layer of the support structure, the plurality of trenches surrounding an active region of the semiconductor region;
three first semiconductor contact regions of the first conductivity type, the first semiconductor contact regions being arranged in the active region of the semiconductor region and are spaced apart from one another;
a first metallic connection contact layer arranged on each the first semiconductor contact regions;
at least one second semiconductor contact region of a second conductivity type, each second semiconductor contact region extending at least partially along the trench and is spaced from the first semiconductor contact regions; and
a second metallic connection contact layer arranged on each second semiconductor contact region,
wherein at least regions of the semiconductor region that extend between the first semiconductor contact regions or an entirety of the semiconductor region are free of threshold voltage implantation.

20. An isolating Hall sensor structure comprising:
a support structure formed of a substrate layer and an oxide layer;
a semiconductor region of a first conductivity type that is integrally connected to a top side of the oxide layer;
a plurality of trenches each extending from the top side of the semiconductor region to the oxide layer of the support structure, the plurality of trenches surrounding a box region (active region) of the semiconductor region;
at least three first semiconductor contact regions of the first conductivity type, the first semiconductor contact regions being arranged in the box region of the semiconductor region and are spaced apart from one another;
a first metallic connection contact layer arranged on each the first semiconductor contact regions;
at least one second semiconductor contact region of a second conductivity type, each second semiconductor contact region extending at least partially along each of the plurality of trenches and is spaced from the first semiconductor contact regions; and
a second metallic connection contact layer arranged on each second semiconductor contact region,
wherein at least regions of the semiconductor region that extend between the first semiconductor contact regions or an entirety of the semiconductor region are free of threshold voltage implantation, and
wherein the first semiconductor contact regions are each spaced apart from the trench.

Assignees

• Tdk Micronas Gmbh

Inventors

• Vecchi Maria-Cristina
• Erwe Reinhard
• Cornils Martin
• Khu Kerwin

Classifications

• G01R33/066

  field-effect magnetic sensors, e.g. magnetic transistor · CPC title

• G01R33/07 Primary

  Hall effect devices · CPC title

• G01R15/202

  using Hall-effect devices (Hall elements in arrangements for measuring electrical power G01R21/08) · CPC title

• H01L43/04

  Electricity · mapped topic

• H01L43/065

  Electricity · mapped topic