FLOWABLE SILICON-AND-CARBON-CONTAINING LAYERS FOR SEMICONDUCTOR PROCESSING

• US 20130217239A1
• Filed: 08/20/2012
• Published: 08/22/2013
• Est. Priority Date: 09/09/2011
• Status: Abandoned Application

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Mallick, Abhijit Basu, Ingle, Nitin K.
• Application Number:
  US13/589,528
• Publication Number:
  US 20130217239A1
• Time in Patent Office: Days
• US Class Current: 438/778
• CPC Class Codes: H01L 21/02123 the material containing silicon
• CPC Class Codes: H01L 21/02167 the material being a silicon carbide not containing oxygen, e.g. SiC, SiC:H or silicon carbonitrides H01L21/02126 and H01L21/0214 take precedence
• CPC Class Codes: H01L 21/02211 the compound being a silane, e.g. disilane, methylsilane or chlorosilane
• CPC Class Codes: H01L 21/02271 deposition by decomposition or reaction of gaseous or vapour phase compounds, i.e. chemical vapour deposition H01L21/02266 takes precedence
• CPC Class Codes: H01L 21/02274 in the presence of a plasma [PECVD]
• CPC Class Codes: H01L 21/02348 treatment by exposure to UV light
• CPC Class Codes: H01L 21/76837 Filling up the space between adjacent conductive structures; Gap-filling properties of dielectrics

Abstract

Methods are described for forming and curing a gapfill silicon-and-carbon-containing layer on a semiconductor substrate. The silicon and carbon constituents may come from a silicon-and-carbon-containing precursor excited by a radical hydrogen precursor that has been activated in a remote plasma region. Exemplary precursors include 1,3,5-trisilapentane (H₃Si—CH₂—SiH₂—CH₂—SiH₃) as the silicon-and-carbon-containing precursor and hydrogen (H₂) as the hydrogen-containing precursor. The hydrogen-containing precursor may also be a hydrocarbon, such as acetylene (C₂H₂) or ethylene (C₂H₄). The hydrogen-containing precursor is passed through a remote plasma region to form plasma effluents (the radical hydrogen precursor) which are flowed into the substrate processing region. When the silicon-and-carbon-containing precursor combines with the plasma effluents in the substrate processing region, they form a flowable silicon-carbon-and-hydrogen-containing layer on the semiconductor substrate.

Claims

1. A method of forming a silicon-and-carbon-containing layer on a semiconductor substrate, the method comprising:

flowing a hydrogen-containing precursor into a remote plasma region to produce a hydrogen-containing plasma effluents,

combining a silicon-and-carbon-containing precursor with the hydrogen-containing plasma effluents in a substrate processing region which contains the semiconductor substrate,

forming a silicon-carbon-and-hydrogen-containing layer over the semiconductor substrate, wherein the silicon-carbon-and-hydrogen-containing layer is initially flowable during deposition and the substrate processing region is plasma-free during formation of the silicon-carbon-and-hydrogen-containing layer, and

treating the silicon-carbon-and-hydrogen-containing layer to form the silicon-and-carbon-containing layer on the semiconductor substrate.

2. The method of claim 1 wherein the silicon-and-carbon-containing layer, the hydrogen-containing plasma effluents and the silicon-and-carbon-containing precursor are essentially devoid of oxygen.

3. The method of claim 1 wherein the silicon-and-carbon-containing layer is essentially devoid of hydrogen.

4. The method of claim 1 wherein the silicon-and-carbon-containing layer is silicon carbide.

5. The method of claim 1 wherein the silicon-and-carbon-containing layer, the hydrogen-containing plasma effluents and the silicon-and-carbon-containing precursor are essentially devoid of nitrogen.

6. The method of claim 1 wherein the hydrogen-containing plasma effluents and the silicon-and-carbon-containing precursor are essentially devoid of nitrogen.

7. The method of claim 1 wherein the silicon-and-carbon-containing precursor comprises 1,3,5-trisilapentane, 1,4,7-trisilaheptane, disilacyclobutane, trisilacyclohexane, 3-methylsilane, silacyclopentene, silacyclobutene, or trimethylsilylacetylene.

8. The method of claim 1 wherein the silicon-and-carbon-containing precursor comprises:

(i) SiR₄, Si₂R₆, Si₃R₈, Si₄R₁₀, or Si₅R₁₂, wherein each R group is independently hydrogen (—

H) or a saturated or unsaturated alkyl group;

(ii) a silylalkane or silylalkene having the formula R₃Si—

[CH₂]_n—

SiR₃, wherein n may be an integer from 1 to 10, and each of the R groups are independently a hydrogen (—

H), or a saturated or unsaturated alkyl group;

(iii) a silylalkane or silylalkene having the formula R₃Si—

[CR₂]_x—

SiR₂—

[CR₂]_y—

SiR₃, wherein x and y are independently an integer from 1 to 10, and each of the R groups are independently a hydrogen (—

H), or a saturated or unsaturated alkyl group;

(iv) a silacycloalkane or silacycloalkene selected from the group consisting of silacyclopropanes, silacyclobutanes, silacyclopentanes, silacyclohexanes, silacycloheptanes, silacyclooctanes, silacyclononanes, silacyclopropenes, silacyclobutenes, silacyclopentenes, silacyclohexenes, silacycloheptenes, silacyclooctenes, and silacyclononenes;

(v) H_4-x-yCX_y(SiR₃)_x, where x is 1, 2, 3, or 4, y is 0, 1, 2 or 3, each X is independently a hydrogen or halogen (e.g., F, Cl, Br), and each R is independently a hydrogen (—

H) or an alkyl group;

(vi) (SiR₃)_xC═

C(SiR₃)_x, where x is 1 or 2, and each R is independently a hydrogen (—

H) or an alkyl group;

or

(vii) R—

[(CR′

₂)_x—

(SiR″

₂)_y—

(CR′

₂)_z]—

R, wherein each R, R′

, and R″

are independently a hydrogen, an alkyl group, an unsaturated alkyl group, a silane group, or

—

[(CH_z)_x1—

(SiH₂)_y1—

(CH₂)_z1]_n1—

R′

″

wherein x1, y1 and z1 are independently a number from 0 to 10, and n1 is a number from 0 to 10,

wherein x, y and z are independently a number from 0 to 10, and n is a number from 0 to 10.

9. The method of claim 1 wherein the silicon-carbon-and-hydrogen-containing layer comprises Si—

H bonds and treating the silicon-carbon-and-hydrogen-containing layer comprises reducing the concentration of Si—

H bonds.

10. The method of claim 1 wherein the treating the silicon-carbon-and-hydrogen-containing layer comprises increasing the concentration of Si—

C bonds.

11. The method of claim 1 wherein the treating of the silicon-carbon-and-hydrogen-containing layer comprises exposing the silicon-carbon-and-hydrogen-containing layer to a plasma.

12. The method of claim 11 wherein the plasma for treating the silicon-carbon-and-hydrogen-containing layer is located in the substrate processing region.

13. The method of claim 11 wherein the plasma is an inductively-coupled plasma or a capacitively-coupled plasma.

14. The method of claim 1 wherein the semiconductor substrate is patterned and has a trench having a width of about 50 nm or less.

15. The method of claim 1 wherein the WERR of the silicon-and-carbon-containing layer relative to silicon oxide is less than 1:

100 in a hydrofluoric acid or phosphoric acid solution.

16. The method of claim 1 wherein the WERR of the silicon-and-carbon-containing layer relative to silicon is less than 1:

100 in a hydrofluoric acid or phosphoric acid solution.

17. The method of claim 1 wherein the hydrogen-containing precursor comprises hydrogen.

18. The method of claim 1 wherein the temperature of the semiconductor substrate is below or about 400°

C. while forming the silicon-carbon-and-hydrogen-containing layer.

19. The method of claim 1 wherein the hydrogen-containing precursor comprises at least one of C₂H₂ or C₂H₄.

20. The method of claim 1 wherein the silicon-and-carbon-containing layer contains at least 40% carbon.