FABRICATING RAISED FINS USING ANCILLARY FIN STRUCTURES

• US 20150332972A1
• Filed: 05/16/2014
• Published: 11/19/2015
• Est. Priority Date: 05/16/2014
• Status: Active Grant

• Current Assignee: Alsephina Innovations Inc. (Quarterhill Inc. (f/k/a Wi-LAN Inc.))
• Original Assignee: GlobalFoundries, Inc.
• Inventors: WU, Xusheng, CHI, Min-hwa, PENG, Jianwei
• Granted Patent: US 9,490,174 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01L 21/02521 Materials
• CPC Class Codes: H01L 21/02529 Silicon carbide
• CPC Class Codes: H01L 21/02532 Silicon, silicon germanium, germanium
• CPC Class Codes: H01L 21/02538 Group 13/15 materials
• CPC Class Codes: H01L 21/823431 with a particular manufacturing method of transistors with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET
• CPC Class Codes: H01L 21/823437 with a particular manufacturing method of the gate conductors, e.g. particular materials, shapes
• CPC Class Codes: H01L 21/823475 interconnection or wiring or contact manufacturing related aspects
• CPC Class Codes: H01L 29/66795 with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET
• CPC Class Codes: H01L 29/6681 using dummy structures having essentially the same shape as the semiconductor body, e.g. to provide stability
• CPC Class Codes: H01L 29/785 having a channel with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET

Abstract

A method of fabricating a raised fin structure including a raised contact structure is provided. The method may include: providing a base fin structure; providing at least one ancillary fin structure, the at least one ancillary fin structure contacting the base fin structure at a side of the base fin structure; growing a material over the base fin structure to form the raised fin structure; and, growing the material over the at least one ancillary fin structure, wherein the at least one ancillary fin structure contacting the base fin structure increases a volume of material grown over the base fin structure near the contact between the base fin structure and the at least one ancillary fin structure to form the raised contact structure.

Claims

1. A method comprising:

fabricating a raised fin structure, the raised fin structure comprising a raised contact structure, comprising;

providing a base fin structure;

providing at least one ancillary fin structure, the at least one ancillary fin structure contacting the base fin structure at a side of the base fin structure;

growing a material over the base fin structure to form the raised fin structure; and

,

growing the material over the at least one ancillary fin structure, wherein the at least one ancillary fin structure contacting the base fin structure increases a volume of material grown over the base fin structure near the contact between the base fin structure and the at least one ancillary fin structure to form the raised contact structure.

2. The method of claim 1, wherein the raised contact structure comprises an upper surface having a convex shape.

3. The method of claim 2, wherein the convex shape comprises a pyramid shape.

4. The method of claim 2, further comprising providing a conductive contact over the raised contact structure to form a contact interface between the upper surface of the raised contact structure and the conductive contact, wherein the convex shape of the upper surface facilitates maximizing a surface area of the contact interface between the upper surface of the raised contact structure and the conductive contact.

5. The method of claim 4, wherein providing the conductive contact comprises a silicidation process, wherein the silicidation process comprises at least providing an oxide material over the raised fin structure and etching to remove a portion of the oxide material from over at least the raised contact structure, wherein the convex shape of the raised contact structure facilitates preventing incomplete removal of the portion of the oxide material.

6. The method of claim 1, wherein the base fin structure comprises a base material and the at least one ancillary fin structure comprises the base material, and wherein the material grown over the base fin structure and the at least one ancillary fin structure is different from the base material.

7. The method of claim 1, wherein the base fin structure comprises a first base material and the at least one ancillary fin structure comprises a second base material, and wherein the material grown over the base fin structure and the at least one ancillary fin structure is different from the first base material and the second base material.

8. The method of claim 1, wherein the material comprises one or more of silicon-phosphorous, silicon-boron, silicon carbide, silicon-germanium, or a column III-V material.

9. The method of claim 1, wherein growing the material comprises epitaxially growing the material.

10. The method of claim 1, wherein the at least one ancillary fin structure perpendicularly contacts a side of the base fin structure.

11. The method of claim 1, wherein the at least one ancillary fin structure comprises a first ancillary fin structure contacting the base fin structure at a first side of the base fin structure, and the method further comprises:

providing a second ancillary fin structure, the second ancillary fin structure contacting the base fin structure at a second side of the base fin structure, the second side of the base fin structure being opposite to the first side thereof; and

,

growing the material over the second ancillary fin structure, wherein the second ancillary fin contacting the base fin structure further increases the volume of material grown over the base fin structure near the contact between the base fin structure and second ancillary fin structure to form the raised contact structure.

12. The method of claim 11, wherein the first ancillary fin structure and the second ancillary fin structure are separated by the base fin structure.

13. The method of claim 1, wherein the base fin structure is a first base fin structure and the raised fin structure is a first raised fin structure, and the method further comprises:

providing a second base fin structure, the at least one ancillary fin structure further contacting the second base fin structure at a side of the second base fin structure; and

,

growing the material over the second base fin structure to form a second raised fin structure, wherein the at least one ancillary fin structure contacting the second base fin structure further increases a volume of material grown over the second base fin structure near the contact between the second base fin structure and the at least one ancillary fin structure to form a second raised contact structure on the second raised fin structure.

14. The method of claim 1, wherein the fabricating further comprises providing at least one gate structure, the at least one gate structure extending transversely over the base fin structure.

15. The method of claim 14, wherein growing the material further comprises growing the material for a time T to form the raised contact structure to a height H, wherein growing the material for the time T over the base fin structure further forms a contact interface between the raised fin structure and the at least one gate structure, wherein a size of contact interface is dependent on time T, and wherein growing the material over the at least one ancillary fin structure facilitates minimizing the time T for forming the raised contact structure to the height H to further minimize the size of the contact interface.

16. The method of claim 14, wherein the at least one gate structure comprises a first gate structure, and the method further comprises providing a second gate structure extending transversely over the base fin structure, wherein the at least one ancillary fin structure contacts the base fin structure intermediate the first gate structure and the second gate structure extending transversely over the base fin structure.

17. The method of claim 14, wherein the at least one ancillary fin structure comprises a primary ancillary fin structure, and the fabricating further comprises providing a secondary ancillary fin structure, the secondary ancillary fin structure also contacting the base fin structure at a side of the base fin structure, and wherein the at least one gate structure is provided over the secondary ancillary fin structure.

18. The method of claim 17, wherein the secondary ancillary fin structure contacting the base fin structure facilitates minimizing a channel resistance of the at least one gate structure and further facilitates increasing drive current.

19. The method of claim 17, wherein the at least one secondary ancillary fin structure facilitates activation and de-activation of the at least one gate structure.

20. The method of claim 17, wherein the at least one gate structure is designed to be operated at a low voltage, and wherein the at least one secondary ancillary fin structure facilitates minimizing current leakage when the at least one gate structure is operated at the low voltage.