METHOD OF FORMING A RECESS STRUCTURE, A RECESSED CHANNEL TYPE TRANSISTOR HAVING THE RECESS STRUCTURE, AND METHOD OF MANUFACTURING THE RECESSED CHANNEL TYPE TRANSISTOR

摘要

A method for forming a recess structure is provided to reduce a junction leakage current and increase the length of an effective channel of a transistor by reducing the junction width of a source/drain region. A first etch process is performed on a substrate(100) to form a first recess(130). A passivation layer pattern(138) is formed on the sidewall of the first recess, made of a material having etch selectivity with respect to the substrate. By using the passivation layer pattern as an etch mask, the substrate under the first recess is etched by a second etch process using etch gas including SF6 gas, Cl2 gas and O2 gas so as to form a second recess(140) having a greater width than that of the first recess. The first etch process is an anisotropic etch process, and the second etch process is an isotropic etch process.