Metal silicide, metal germanide, methods for making the same

• US 10,043,880 B2
• Filed: 04/20/2017
• Issued: 08/07/2018
• Est. Priority Date: 04/22/2011
• Status: Active Grant

• Current Assignee: ASM International NV
• Original Assignee: ASM International NV
• Inventors: Pore, Viljami J., Haukka, Suvi P., Blomberg, Tom E., Tois, Eva E.
• Primary Examiner(s): Ahmadi, Mohsen
• Application Number:
  US15/492,892
• Publication Number:
  US 20170352737A1
• Time in Patent Office: 474 Days
• CPC Class Codes: C23C 16/06 characterised by the deposition of metallic material
• CPC Class Codes: C23C 16/406 of iron group metals
• CPC Class Codes: C23C 16/45527 characterized by the ALD cycle, e.g. different flows or temperatures during half-reactions, unusual pulsing sequence, use of precursor mixtures or auxiliary reactants or activations
• CPC Class Codes: H01L 21/28518 the conductive layers comprising silicides H01L21/28537 takes precedence
• CPC Class Codes: H01L 21/28556 by chemical means, e.g. CVD, LPCVD, PECVD, laser CVD H01L21/28518 - H01L21/28537 and H01L21/28568 take precedence
• CPC Class Codes: H01L 21/28562 Selective deposition
• CPC Class Codes: H01L 21/3215 Doping the layers
• CPC Class Codes: H01L 21/324 Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering H01L21/20 - H01L21/288 and H01L21/302 - H01L21/322 take precedence
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76855 After-treatment introducing at least one additional element into the layer
• CPC Class Codes: H01L 29/45 Ohmic electrodes
• CPC Class Codes: H01L 29/456 on silicon
• CPC Class Codes: H01L 29/4933 with a silicide layer contacting the silicon layer, e.g. Polycide gate with a barrier layer between the silicide and silicon layers H01L29/4941
• CPC Class Codes: H01L 29/665 using self aligned silicidation, i.e. salicide formation of conductive layers comprising silicides H01L21/28518
• CPC Class Codes: H01L 29/66666 Vertical transistors H01L29/66712, H01L29/66742 take precedence
• CPC Class Codes: H01L 29/7827 Vertical transistors H01L29/7802, H01L29/78642 take precedence

Abstract

In one aspect, methods of silicidation and germanidation are provided. In some embodiments, methods for forming metal silicide can include forming a non-oxide interface, such as germanium or solid antimony, over exposed silicon regions of a substrate. Metal oxide is formed over the interface layer. Annealing and reducing causes metal from the metal oxide to react with the underlying silicon and form metal silicide. Additionally, metal germanide can be formed by reduction of metal oxide over germanium, whether or not any underlying silicon is also silicided. In other embodiments, nickel is deposited directly and an interface layer is not used. In another aspect, methods of depositing nickel thin films by vapor phase deposition processes are provided. In some embodiments, nickel thin films are deposited by ALD.

Claims

1. A method for depositing an elemental cobalt (Co) thin film, the method comprising:

providing a substrate comprising a 300 mm wafer in a reaction space of a flow type reactor, wherein the substrate comprises a silicon surface;

carrying out one or more deposition cycles at a growth temperature of less than about 400°

C., the deposition cycle comprising;

contacting the silicon surface of the substrate with a first vapor phase metal precursor comprising cobalt;

removing excess first vapor phase metal precursor from the reaction space;

contacting the substrate comprising the silicon surface and the cobalt with a second vapor phase reactant such that it reacts with the first vapor phase metal precursor to form elemental cobalt (Co);

wherein the elemental cobalt (Co) thin film is deposited directly on the silicon surface of the substrate;

subsequently depositing a thin film comprising a dopant over the elemental cobalt (Co) thin film; and

annealing the substrate comprising the elemental cobalt (Co) thin film and the thin film comprising the dopant to form a doped cobalt silicide layer.

2. The method of claim 1, wherein the first vapor phase metal precursor is a metal compound in which the metal is bound or coordinated to oxygen, nitrogen, carbon or a combination thereof.

3. The method of claim 1, wherein the first vapor phase metal precursor is an organic compound.

4. The method of claim 3, wherein the first vapor phase metal precursor is a betadiketonate, betadiketiminato compounds, amidinate compounds, aminoalkoxide, ketoiminate or cyclopentadienyl compound.

5. The method of claim 3, wherein the first vapor phase metal precursor is a cyclopentadienyl cobalt compound.

6. The method of claim 3, wherein the first vapor phase metal precursor is a compound with the formula X(acac)y, where X is cobalt and y is between 2 and 3.

7. The method of claim 3, wherein the first vapor phase metal precursor is a compound with the formula X(thd)y, where X is cobalt, y is between 2 and 3 and thd is 2,2,6,6-tetramethyl-3,5-heptanedionato.

8. The method of claim 1, wherein the method is an atomic layer deposition (ALD) method.

9. The method of claim 8, wherein the ALD method comprises alternately and sequentially contacting the substrate with the first vapor phase metal precursor and the second vapor phase reactant.

10. The method of claim 1, wherein the growth temperature is less than about 200°

C.

11. The method of claim 1, wherein the first vapor phase metal precursor is pulsed into the reaction space for from about 0.3 to 3 seconds.

12. The method of claim 1, wherein the dopant is a metal.

13. The method of claim 12, wherein the dopant is platinum.

14. The method of claim 1, wherein the dopant content in the doped cobalt silicide layer as a percentage of the overall metal content is about 0-10%.