Micron Technology Incorporated

Yong-Jun Hu

Pai-Hung Pan

Pai Hung Pan

Mark Klare

A method of controlling stresses in thin films that are deposited over semiconductor device substrates. During anneal process steps, grain growth of the film creates stresses in that can damage or destroy it. The stresses lead to warping and bowing and ultimately to film cracking which undermines desired low resistivity. The present invention imparts thermal stability to thin films by grain boundary stuffing (GBS) of preselected elements that resist film grain changes that cause the stresses. GBS implants the elements into the thin film at desired depths, but above the film-substrate interface, sufficient to prevent or lessen destructive grain growth. GBS provides for structural film stability required during severe thermal cycles that occur during subsequent processing of semiconductor devices.

Multiple implantation and grain growth method

A semiconductor device on a semiconductor wafer and the devices made by the method, wherein improvements are realized to agglomeration control, resistivity, and thermal stability of a titanium disilicide layer on a polysilicon layer. Agglomeration control is achieved through the use of two carefully selected low dose barrier diffusion matrix implants into the polysilicon layer, one of which is situated at an interface between the layer of polysilicon and the resultant layer of titanium disilicide film after heat treatment, and the other of which is near the surface of the resultant layer of titanium disilicide film after heat treatment.

Second implant for agglomeration control

Metal silicide film stress control by grain boundary stuffing

A novel compound PVD target material, suitable for use in the fabrication of cobalt silicide layers on semiconductor devices is disclosed. The compound material is formed by blending an amount of SiO.sub.z with an amount of CoSi.sub.x to form a blended compound material CoSi.sub.x O.sub.y and then compressing and shaping said blended compound material in a hot powder press into an appropriate shape for use in a PVD sputtering chamber. A polysilicon MOSFET gate stack structure and a source/drain salicide structure incorporating the CoSi.sub.x O.sub.y compound material are described. The addition of a small amount of oxide to the cobalt silicide, when sputter deposited, results in an as-deposited film of CoSi.sub.x O.sub.y having smaller grain size and significantly enhanced thermal stability over conventional CoSi.sub.x, and other characteristics desirable in the fabrication of salicide MOSFET structures.

Method for fabricating a structure on a cobalt silicide oxide

Sputtered metal silicide film stress control by grain boundary stuffing

A semiconductor device on a semiconductor wafer, wherein improvements are realized to agglomeration control, resistivity, and thermal stability of a titanium disilicide layer on a polysilicon layer. Agglomeration control is achieved through the use of two carefully selected low dose barrier diffusion matrix implants into the polysilicon layer, one of which is situated at an interface between the layer of polysilicon and the resultant layer of titanium disilicide film after heat treatment, and the other of which is near the surface of the resultant layer of titanium disilicide film after heat treatment.

Second implanted matrix for agglomeration control and thermal stability

A novel compound PVD target material, suitable for use in the fabrication of cobalt silicide layers on semiconductor devices is disclosed. The compound material is formed by blending an amount of SiO.sub.z with an amount of CoSi.sub.x to form a blended compound material CoSi.sub.x O.sub.y and then compressing and shaping said blended compound material in a hot powder press into an appropriate shape for use in a PVD sputtering chamber. A polysilicon MOSFET gate stack structure and a source/drain salicide structure incorporating the CoSi.sub.X O.sub.y, compound material are described. The addition of a small amount of oxide to the cobalt silicide, when sputter deposited, results in an as-deposited film of CoSi.sub.x O.sub.y having smaller grain size and significantly enhanced thermal stability over conventional CoSi.sub.x, and other characteristics desirable in the fabrication of salicide MOSFET structures.

Growing community of inventors

Boise, ID, United States of America

Yong-Jun Hu