초록 ▼

An improved SALICIDE process is described wherein the transformation temperature to a lower resistivity suicide structure is reduced by first coating with a layer of a silicon-germanium alloy prior to the deposition of the titanium layer. Provided there is at least 40 atomic percent of germanium in

An improved SALICIDE process is described wherein the transformation temperature to a lower resistivity suicide structure is reduced by first coating with a layer of a silicon-germanium alloy prior to the deposition of the titanium layer. Provided there is at least 40 atomic percent of germanium in the alloy a second RTA at a temperature no higher than about 650.degree. C. may be effectively used. The resulting ternary alloy has a resistivity of about 15-20 microhm cm which corresponds to a sheet resistance of about 3-3.5 ohms per square. The ability to achieve low sheet resistance after annealing at such a low temperature becomes increasingly more important as device dimensions decrease since the second RTA becomes increasingly more likely to result in agglomeration of the silicidelayer.

대표청구항 ▼

1. A selective contacting process comprising:providing a silicon body having a top surface which includes at least one area of silicon oxide; depositing a layer of silicon-germanium alloy, containing between 50 and 69.9 atomic percent of germanium, on the silicon top surface; depositing a layer of t

1. A selective contacting process comprising:providing a silicon body having a top surface which includes at least one area of silicon oxide; depositing a layer of silicon-germanium alloy, containing between 50 and 69.9 atomic percent of germanium, on the silicon top surface; depositing a layer of titanium on said silicon-germanium layer; subjecting the silicon body to a first rapid thermal anneal, thereby causing the titanium that is in contact with said silicon-germanium layer to form a layer of titanium-silicon-germanium alloy having a first sheet resistance value; selectively removing all unreacted titanium; and subjecting said silicon body to a second rapid thermal anneal for between about 20 and 40 seconds at a temperature between 650 and 699.9.degree. C., whereby a change in crystalline form occurs and said titanium-silicon-germanium alloy has its resistivity reduced to between about 15 and 20 micro-ohm-cm.