Method of forming amorphous TiN by thermal chemical vapor deposition (CVD)
US7732307B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 3, 2005 |
| Grant date | Jun 8, 2010 |
| Priority date | — |
| Expiry date | Jun 3, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S257/915
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A modified TDEAT (tetrakisdiethylamino titanium) based MOCVD precursor for deposition of thin amorphous TiN:Si diffusion barrier layers. The TDEAT is doped with 10 at % Si using TDMAS (trisdimethlyaminosilane); the two liquids are found to form a stable solution when mixed together. Deposition occurs via pyrolysis of the vaporised precursor and NH3 on a heated substrate surface. Experimental results show that we have modified the precursor in such a way to reduce gas phase component of the deposition when compared to the unmodified TDEAT-NH3 reaction. Deposition temperatures were the range of 250-450° C. and under a range of process conditions the modified precursor shows improvements in coating conformality, a reduction in resistivity and an amorphous structure, as shown by TEM and XRD analysis. SIMS and scanning AES have shown that the film is essentially stoichiometric in Ti:N ratio and contains low levels of C (˜0.4 at %) and trace levels of incorporated Si (0.01<Si<0.5 at %).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.