Tungsten tunnel-free process
US5698466A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 1996 |
| Grant date | Dec 16, 1997 |
| Priority date | — |
| Expiry date | Dec 16, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of forming a tunnel-free tungsten plug is described. Semiconductor device structures are provided in and on a semiconductor substrate. An insulating layer of borophospho-tetraethoxysilane (BP-TEOS) is deposited overlying the semiconductor device structures. Contact openings are etched through the insulating layer to the underlying semiconductor device structures wherein a tunnel opens in the insulating layer between contact openings. The semiconductor substrate is covered with a first barrier metal layer. The semiconductor substrate is coated with a spin-on-glass layer wherein the contact openings and the tunnel are filled with the spin-on-glass. The spin-on-glass is anisotropically etched away whereby the spin-on-glass remains only within the tunnel. The semiconductor substrate is covered with a second barrier metal layer. The contact openings are filled with tungsten which is etched back to form tungsten plugs within the contact openings wherein the filled tunnel provides tunnel-free tungsten plugs in the fabrication of the integrated circuit device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.