Boron profiles and interface characteristics of SiO2/Si structure when boron was implanted by high energy implantation were studied. A very narrow (similar to0.3 mum) channel-stop layer can be formed under a 1.5 mum thick SiO2 layer by high energy B+ implantation. An ion dose of 1.5 x 10(12) ions/cm(2) is adequate to form a channel-stop layer. The surface state density was 2.2 x 10(11)/cm(2) after implantation and decreased to a value of 1 x 10(11)/cm(2) following 1 h of heat-treatment at 1000degreesC. The surface state density was decreased by heat-treatment and recovered to a value equal to that of nonimplanted samples.