Systems and methods for a tunable electromagnetic field apparatus to improve doping uniformity

Patent metadata

Field	Value
Publication number	US-10170313-B2
Application number	US-201615143824-A
Country	US
Kind code	B2
Filing date	May 2, 2016
Priority date	May 2, 2016
Publication date	Jan 1, 2019
Grant date	Jan 1, 2019

Abstract

Systems and methods for improving doping and/or deposition uniformity using a tunable electromagnetic field generation device are provided. In an exemplary embodiment, the system includes a chamber configured to contain a semiconductor wafer, a plasma generator, and a gas inlet, and an exhaust gas outlet. The gas inlet permits a controlled flow of a gas into the chamber through a wall of the chamber and the exhaust gas outlet permits exhausting of gas from the chamber. The system further includes a wafer support structure configured to support the semiconductor wafer during a doping or deposition process and an electromagnetic structure positioned within the chamber and at least partially surrounding an upper surface of the wafer support structure.

First claim

What is claimed is:

1. A semiconductor manufacturing system comprising:
a chamber configured to contain a semiconductor wafer;
a plasma generator;
a gas inlet, the gas inlet permitting a controlled flow of a gas into the chamber through a wall of the chamber;
an exhaust gas outlet, the exhaust gas outlet permitting exhausting of gas from the chamber;
a wafer support structure configured to support the semiconductor wafer during a deposition process; and
an electromagnetic structure positioned within the chamber and surrounding the wafer support structure, wherein the electromagnetic structure comprises a plurality of electromagnetic elements whose positions are movable independently of each other.

2. The semiconductor manufacturing system of claim 1 , wherein the electromagnetic elements surround the wafer support structure.

3. The semiconductor manufacturing system of claim 1 , wherein a lower edge of the electromagnetic structure is positioned higher than a top of the wafer support structure.

4. The semiconductor manufacturing system of claim 1 , wherein the plurality of electromagnetic elements each comprise a core structure that is encircled by windings of conductive wire.

5. The semiconductor manufacturing system of claim 4 , wherein the core structure comprises a magnetic material and the windings comprise copper wire.

6. The semiconductor manufacturing system of claim 4 , wherein the windings are coupled to a control system configured to controllably vary a current flowing through the windings to alter the deposition process performed within the chamber.

7. The semiconductor manufacturing system of claim 1 , further comprising one or more electromagnetic sensors disposed within the chamber to measure a magnetic field generated by the electromagnetic structure.

8. A dopant tool comprising:
a chamber sized to contain a wafer;
a plasma generator to accelerate particles toward a wafer support structure; and
an electromagnetic structure disposed between the plasma generator and the wafer support structure, the electromagnetic structure encircling the wafer support structure, wherein the electromagnetic structure comprises a plurality of electromagnetic elements whose positions are movable independently of each other.

9. The dopant tool of claim 8 , wherein the plurality of electromagnetic elements comprises a first electromagnetic element and a second electromagnetic element, wherein the first and second electromagnetic elements are positioned opposite each other relative to a central axis of a shaft coupled to the wafer support structure, and wherein each of the first and second electromagnetic elements has about a half-circle shape or a quarter-circle shape.

10. The dopant tool of claim 9 , wherein the first and second electromagnetic elements are separated by a first gap between first ends of the first and second electromagnetic elements and by a second gap between second ends of the first and second electromagnetic elements.

11. The dopant tool of claim 10 , wherein the first and second electromagnetic elements each comprise a core structure with a conductive wire that is looped therearound such that a first conductive wire is looped around the first electromagnetic element and a second conductive wire is looped around the second electromagnetic element.

12. The dopant tool of claim 11 , further comprising a control system coupled to the first and second conductive wires and configured to independently control a first current flowing through the first conductive wire and a second current flowing through the second conductive wire.

13. The dopant tool of claim 8 , wherein the plurality of electromagnetic elements comprises a first electromagnetic element and a second electromagnetic element positioned along a central axis such that the second electromagnetic element is positioned closer to the wafer support structure than is the first electromagnetic element.

14. The dopant tool of claim 8 , wherein the plurality of electromagnetic elements comprises four core structures, each core structure separated from two neighboring core structures by a gap, and each core structure having a quarter-circle shape.

15. The dopant tool of claim 8 , wherein a lower edge of the electromagnetic structure is below a top surface of the wafer support structure.

16. The dopant tool of claim 8 , wherein the wafer support structure moves along a central axis of a shaft to a loading position above a top edge of the electromagnetic structure.

17. The dopant tool of claim 8 , further comprising a gas inlet, whereby a dopant gas is introduced into the chamber during a doping process.

18. The dopant tool of claim 11 , wherein the core structure comprises a magnetic material.

19. The dopant tool of claim 18 , wherein each conductive wire is a copper wire coupled to a control system.

20. The dopant tool of claim 8 , further comprising one or more electromagnetic sensors disposed within the chamber to measure a magnetic field generated by the electromagnetic structure.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Lai Chien-An
• Wu Joseph
• Ku Wen-Yu

Classifications

• H10P32/1204 Primary

  from a plasma phase · CPC title

• H01J37/32009

  Arrangements for generation of plasma specially adapted for examination or treatment of objects, e.g. plasma sources (plasma generation in general H05H1/24) · CPC title

• H01L21/2236 Primary

  Electricity · mapped topic

• H01J2237/334

  Etching · CPC title

• H01J37/32449

  Gas control, e.g. control of the gas flow · CPC title