Semiconductor component with embedded fixed charges to provide increased high breakdown voltage

• US 5,767,548 A
• Filed: 03/29/1996
• Issued: 06/16/1998
• Est. Priority Date: 10/01/1993
• Status: Expired due to Fees

• Current Assignee: Daimler-Benz AG (Mercedes-Benz Group AG)
• Original Assignee: Daimler-Benz AG (Mercedes-Benz Group AG)
• Inventors: Held, Raban, Wondrak, Wolfgang
• Primary Examiner(s): LOKE, STEVEN HO YIN
• Application Number:
  US08/619,614
• Time in Patent Office: 809 Days
• Field of Search: 251/347, 251/645, 251/651, 251/500, 251/104
• US Class Current: 257/347
• CPC Class Codes: H01L 29/8611 Planar PN junction diodes

Abstract

A semiconductor component with at least one lateral semiconductor structure with a high breakdown voltage including a substrate, a dielectric layer adjoining the substrate, a low-doped semiconductor zone disposed on the dielectric layer and heavily doped semiconductor zones of the semiconductor component which project into the low-doped semiconductor zone from the direction of the outer surface of the semiconductor component. Fixed charges, which reduce the electrical field strength in the blocking component of the lateral structure, are embedded inside the dielectric layer adjoining the substrate at least opposite that area of the low-doped semiconductor zone which, in the blocking state of the semiconductor component, has a high voltage in respect to the substrate.

Claims

1. A semiconductor component with at least one lateral semiconductor structure with a high breakdown voltage with said component including a substrate, a dielectric layer adjoining the substrate, a low-doped semiconductor zone disposed on the dielectric layer and heavily doped semiconductor zones of the semiconductor component which project into the low-doped semiconductor zone from the direction of an outer surface of the semiconductor component, and wherein fixed charges, which reduce the electrical field strength in a blocking state of the lateral structure, are embedded inside the dielectric layer adjoining the substrate, at least opposite an area of the low-doped semiconductor zone which, in the blocking state of the semiconductor component, has a high voltage in respect to the substrate.

2. A semiconductor component in accordance with claim 1, wherein the heavily doped semiconductor zones include a first semiconductor zone, having a first conductivity type with a higher foreign atom concentration than the low-doped semiconductor zone, and a second semiconductor zone which has a second conductivity type with a foreign atom concentration which is higher than that of the low-doped semiconductor zone and is located outside of the first semiconductor zone, implanted into the low-doped semiconductor zone.

3. A semiconductor component in accordance with claim 1 wherein the fixed charges are disposed homogeneously in a laterally extending layer.

4. A semiconductor component in accordance with claim 1, wherein

the fixed charges are embedded at the highest possible concentration into the dielectric layer underneath one of the heavily doped semiconductor zones which, during blocking operation, have the higher voltage difference in respect to the substrate and their concentration continuously decreases laterally toward the other of the heavily doped semiconductor zones with low voltage difference in respect to the substrate.

5. A semiconductor component in accordance with claim 1, wherein silicon is used as a semiconductor material for the semiconductor portions of the semiconductor component.

6. A semiconductor component in accordance with claim 1, wherein

the dielectric layer consists of AlN, BN, Si₃ N₄ or SiO₂, or of a mixture of these materials.

7. A semiconductor component in accordance with claim 1, wherein

the fixed charges are positive charges.

8. A semiconductor component in accordance with claim 7, wherein

the fixed positive charges are charges provided by implanting positive ions.

9. A semiconductor component in accordance with claim 8, wherein

the positive ions are cesium ions.

10. A semiconductor component in accordance with claim 8, wherein

the positive ions are iodine ions.

11. A semiconductor component in accordance with claim 8, wherein

the positive ions are boron ions.

12. A semiconductor component in accordance with claim 8, wherein

the positive ions are silicon ions.

13. A semiconductor component in accordance with claim 1, wherein:

the dielectric layer has a non-stoichiometric composition; and

, the fixed charges are produced by the non-stoichiometric composition of the dielectric layer.

14. A semiconductor component in accordance with claim 1, wherein

the fixed charges in the dielectric layer are charges produced by irradiation with high-energy particles.