Vertical hall device with highly conductive opposite face node for electrically connecting first and second hall effect regions

Patent metadata

Field	Value
Publication number	US-9252354-B2
Application number	US-201313753195-A
Country	US
Kind code	B2
Filing date	Jan 29, 2013
Priority date	Jan 29, 2013
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

Vertical Hall device with highly conductive node for electrically connecting first and second Hall effect regions. A vertical Hall device comprises a first Hall effect region and a different second Hall effect region, both in a common semiconductor body. The first and second Hall effect regions have a main face and an opposite face, respectively. A highly conductive opposite face node is in ohmic contact to the opposite face of the first Hall effect region and the opposite face of the second Hall effect region in the semiconductor body. The vertical Hall device also comprises a first pair of contacts in or at the main face of the first Hall effect region and a second pair of contacts in or at the main face of the second Hall effect region. A convex circumscribing contour of the second pair of contacts is disjoint from a convex circumscribing contour of the first pair of contacts. Alternative embodiments comprise a pair of contacts and an opposite face node contact.

First claim

The invention claimed is:

1. A vertical Hall device comprising:
a first Hall effect region and a second Hall effect region different from the first Hall effect region, both Hall effect regions in a common semiconductor body, the first Hall effect region and the second Hall effect region having a main face and an opposite face, respectively;
a highly conductive opposite face node in common ohmic contact to the opposite face of the first Hall effect region and to the opposite face of the second Hall effect region in the semiconductor body;
a first pair of contacts in or at the main face of the first Hall effect region; and
a second pair of contacts in or at the main face of the second Hall effect region, wherein a convex circumscribing contour of the second pair of contacts is disjoint from a convex circumscribing contour of the first pair of contacts, in that a straight line between any two points within the contacts of the first pair of contacts does not contain any point within the contacts of the second pair of contacts, and a straight line between any two points within the contacts of the second pair of contacts does not contain any point within the contacts of the first pair of contacts.

2. The vertical Hall device according to claim 1 , wherein a distance of the contacts of at least one of the first pair of contacts and the second pair of contacts is smaller than the depth of at least one of the first Hall effect region and the second Hall effect region, respectively.

3. The vertical Hall device according to claim 1 , wherein a distance of the contacts of the first pair of contacts and a distance of the contacts of the second pair of contacts is smaller than a distance of the first pair of contacts and the second pair of contacts.

4. The vertical Hall device according to claim 1 , wherein during operation an electric current is fed to the first and second Hall effect regions via exactly one contact of the first and second pair of contacts and withdrawn from the first and second Hall effect regions via exactly one other contact of the first and second pair of contacts.

5. The vertical Hall device according to claim 1 , further comprising isolation means between the first Hall effect region and the second Hall effect region.

6. The vertical Hall device according to claim 5 , wherein the isolation means is configured to cause at least 50% of a total electric current to flow via the highly conductive opposite face node from the first Hall effect region to the second Hall effect region, or vice versa.

7. The vertical Hall device according to claim 1 , wherein the contacts of the first pair and the second pair are arranged symmetrically with respect to the first and second Hall effect regions, respectively.

8. The vertical Hall device according to claim 1 , wherein a distance between the first pair and the second pair is larger than the depth of the first Hall effect region and larger than the depth of the second Hall effect region.

9. The vertical Hall device according to claim 1 , wherein a distance between the first pair of contacts and the second pair of contacts extends in a direction orthogonal to the distance between the contacts of the first pair of contacts and also orthogonal to the distance between the contacts of the second pair of contacts.

10. The vertical Hall device according to claim 1 , wherein the first Hall effect region and the second Hall effect region are arranged within a common tub of a doping type within the semiconductor body, and wherein a distance between the first pair of contacts and the second pair of contacts effectively splits the common tub into the first Hall effect region and the second Hall effect region.

11. The vertical Hall device according to claim 1 ,
wherein the first Hall effect region comprises a first medium-doped well, wherein a large part of a contact of the first pair of contacts is overlapped by the first medium-doped well,
wherein the second Hall effect region comprises a second medium-doped well, wherein a large part of a contact of the second pair of contacts is overlapped by the second medium-doped well, and
wherein the first and second medium-doped wells have a doping level that is between a doping level of the contacts and a doping level of the first and second Hall effect regions, and wherein said contacts, said medium-doped wells, and said Hall effect regions are doped with the same type of doping.

12. The vertical Hall device according to claim 11 , wherein a distance between the first medium-doped well and a perimeter of the first Hall effect region is less than 10% of the depth of the first Hall effect region, and wherein a distance between the second medium-doped well and a perimeter of the second Hall effect region is less than 10% of the depth of the second Hall effect region.

13. The vertical Hall device according to claim 1 , wherein the first and second Hall effect regions are formed in an epitaxial layer of the semiconductor body.

14. The vertical Hall device according to claim 1 , wherein the highly conductive node is an n-buried layer in the case of an n-type doping of the Hall effect region and the highly conductive node is a p-buried layer in the case of a p-type doping of the Hall effect region.

15. The vertical Hall device according to claim 1 , wherein the opposite face node comprises a material with a conductivity that is at least ten times higher than the conductivity of the material of the Hall effect region.

16. A sensing arrangement comprising a vertical Hall device and a further vertical Hall device, wherein the vertical Hall device and the further vertical Hall device comprise, respectively:
a first Hall effect region and a second Hall effect region different from the first Hall effect region, both Hall effect regions in a common semiconductor body, the first and second Hall effect regions having a main face and an opposite face, respectively;
a highly conductive opposite face node in common ohmic contact to the opposite faces of the first Hall effect region and of the second Hall effect region in the semiconductor body;
a first pair of contacts in or at the main face of the first Hall effect region; and
a second pair of contacts in or at the main face of the second Hall effect region, wherein a convex circumscribing contour of the second pair of contacts is disjoint from a convex circumscribing contour of the first pair of contacts, in that a straight line between any two points within the contacts of the first pair of contacts does not contain any point within the contacts of the second pair of contacts, and a straight line between any two points within the contacts of the second pair of contacts does not contain any point within the contacts of the first pair of contacts;
wherein the highly conductive opposite face nodes of the vertical Hall device and the further vertical Hall device are not in ohmic contact with each other.

17. A method for sensing a magnetic field parallel to a face of a semiconductor body, the method comprising:
connecting an electrical energy source to a vertical Hall device causing an electric current therein, the vertical Hall device comprising a first Hall effect region with a main face and an opposite face within a semiconductor body, a second Hall effect region with a main face and an opposite face within the semiconductor body, and a highly conductive opposite face node in common ohmic contact to the opposite faces of both the first and second Hall effect regions,
wherein a first pole of the electrical energy source is connected to a first contact belonging to a firs

Assignees

• Infineon Technologies Ag

Inventors

• Ausserlechner Udo

Classifications

• G01R33/075 Primary

  Hall devices configured for spinning current measurements · CPC title

• H01L43/04 Primary

  Electricity · mapped topic

• H01L43/065

  Electricity · mapped topic

• H10N52/101

  Semiconductor Hall-effect devices · CPC title

• H10N52/80 Primary

  Constructional details · CPC title