MANUFACTURING METHOD FOR SEMICONDUCTOR DEVICE

摘要

A method for manufacturing a semiconductor device is provided to prevent degradation of device performance due to impurity diffusion by forming a polycrystalline silicon layer with a low doping concentration and, subsequently, a metal plug. A gate dielectric(32) is formed on a semiconductor substrate(30). A gate electrode(34) overlapped with a hard mask layer(36) pattern is formed on the gate dielectric. Insulating spacers(38) are formed on the hard mask layer pattern and a sidewall of the gate electrode. An interlayer dielectric(40) is formed on the whole surface of the structure. The interlayer dielectric on a portion that is expected as a contact on the semiconductor substrate is removed to form a landing plug contact hole. A selective epi growth polycrystalline silicon layer(42) is formed on the semiconductor substrate exposed through the contact hole by undoping or by lE14 to 1E18/cm^3 impurity doping concentration. Impurity ion is implanted into the selective epi growth polycrystalline silicon layer to form an ohmic contact layer(43). A metal plug is formed to be connected to the ohmic contact layer.