Silicon-doped titanium wetting layer for aluminum plug

Details Silicon-doped titanium wetting layer for aluminum plug Silicon-doped titanium wetting layer for aluminum plug

1997-03-18

1999-06-08

Quach, T. N.

Semiconductor device manufacturing: process

Coating with electrically or thermally conductive material

To form ohmic contact to semiconductive material

438654, 438655, 438688, H01L 2128

Patent

active

059111135

ABSTRACT:
A process for fabricating metal plugs, such as aluminum plugs, in a semiconductor workpiece. The invention is suitable for filling narrow, high aspect ratio holes, and the invention minimizes the formation of TiAl3 or other products of interdiffusion between the plug and the wetting layer. First, an optional barrier layer is created by covering the bottom of a hole with a film containing titanium nitride doped with silicon. Second, a wetting layer is created by covering the side walls of a hole with a film containing titanium doped with silicon, in a Ti:Si molar ratio greater than 1:2. Preferably, the wetting layer is created by sputter deposition using a titanium sputtering target containing 0.1% to 20% wt silicon, most preferably 5% to 10% wt silicon. Third, the hole is filled by depositing a material consisting primarily of aluminum. The hole preferably is filled by sputter deposition using an aluminum sputtering target, optionally containing dopants such as copper. To facilitate filling the hole without voids, the aluminum sputter deposition preferably is performed "warm", i.e., with the workpiece at a temperature below the melting point of aluminum but high enough to promote reflow of the deposited material. The silicon atoms in the wetting layer inhibit the titanium from reacting with the aluminum, and the wetting layer facilitates filling the hole with the aluminum material without leaving unfilled voids.

REFERENCES:
patent: 4663191 (1987-05-01), Choi et al.
patent: 5036382 (1991-07-01), Yamaha
patent: 5043300 (1991-08-01), Nulman
patent: 5108569 (1992-04-01), Gilboa et al.
patent: 5108951 (1992-04-01), Chen et al.
patent: 5171412 (1992-12-01), Talieh et al.
patent: 5242860 (1993-09-01), Nulman et al.
patent: 5250467 (1993-10-01), Somekh et al.
patent: 5266521 (1993-11-01), Lee et al.
patent: 5268329 (1993-12-01), Chittipeddi et al.
patent: 5270254 (1993-12-01), Chen et al.
patent: 5328722 (1994-07-01), Ghanayem et al.
patent: 5362372 (1994-11-01), Tepman
patent: 5371042 (1994-12-01), Ong
patent: 5378660 (1995-01-01), Ngan et al.
patent: 5431799 (1995-07-01), Mosely et al.
patent: 5525543 (1996-06-01), Chen
Murarka, S.P.1 Silicides for VLSI Applications, Academic Press, 1983, pp. 36-43, 78-88, 115-131, 1983.
R.K. Nahar et al., "Effect of Si on the reaction kinetics of Ti/AlSi bilayer structures," Appl. Phys. Lett. 50 (3), pp. 130-131, 1987.
X. Sun et al., "Ti-Si-N diffusion barriers for Al and Cu metallizations," on pp. 401 et seq. of "Advanced Metallization and Interconnect Systems for ULSI Applications," ed. R.C. Ellwanger et al., 1995.
P.R. Besser et al., "Effect of Si on TiAl.sub.3 formation in Ti/Al alloy bilayers," Mat. Res. Soc. Symp. Proc., vol. 355, pp. 631-636, 1995.
X. Sun et al., "Reactively sputtered Ti-Si-N diffusion barriers," Conf. Proc. ULSI XI, pp. 401-408, 1996; paper originally presented at ULSI XI Conference, Oct. 3-5, 1995.

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