ISOLATION METHOD OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: An isolation method of a semiconductor device is provided to be capable of preventing a well punch phenomenon by reinforcing the isolation between a P well and an N-well. CONSTITUTION: After forming a trench(11) at the inner portion of a semiconductor substrate(10), a sacrificial layer is formed along the inner wall of the trench. A channel stop region(22) is formed at the lower portion of the trench by carrying out an Ar ion implantation at the trench region. Then, the sacrificial layer is completely removed. After forming a thermal oxide layer(24) along the inner wall of the trench by carrying out a thermal oxidation process at the resultant structure, an isolation layer(26) is formed at the inner portion of the trench. Then, the first and second well are formed at both sides of the channel stop region in the substrate. Preferably, the Ar ion implantation is carried out by using energy of 30-400 eV.