METHOD OF CONTROLLING THRESHOLD VOLTAGE CAPABLE OF BEING VARIED DUE TO SCATTERING OF IONS IN TRANSISTOR USING ION-IMPLANTATION MASK WITH RECESSED PORTION CORRESPONDING TO ION SCATTERED REGION

摘要

PURPOSE: A method is provided to prevent the variation of a threshold voltage due to scattering of implanted ions by using an ion-implantation mask with a recessed portion corresponding to an ion scattered region. CONSTITUTION: An active region(110) is formed by performing a well ion-implantation on a silicon substrate. A threshold voltage controlling ion-implantation is obliquely performed on the active region by using a mask(116). A gate and a predetermined junction are sequentially formed at the substrate. The mask includes a recessed portion capable of preventing the variation of a threshold voltage due to scattering of implanted ions.