Contact structure for low contact resistance to source/drain regions of p-type MOSFET, has germanium-containing dielectric layer placed over elongated materials, and metal film located over germanium-containing dielectric layer

摘要

The contact structure has a substrate (202) comprising a main surface (202s), and a cavity that is located under the main surface. An elongated material is provided in the cavity, where a lattice constant of the elongated material is different from a lattice constant of the substrate. A germanium-containing dielectric layer is placed over the elongated material. A metal film is located over the germanium-containing dielectric layer. The elongated material consists of silicon-germanium or silicon-germanium-boron. The metal film is formed from cobalt, nickel and titanium nitride. The contact structure comprises a germanium-layer exposed to a vapor such as nitrogen, ammonia, water, oxygen and ozone. Independent claims are also included for the following: (1) a p-type MOSFET (2) a method for manufacturing a semiconductor device.