| 摘要 |
PURPOSE:To realize the same junction depth as in the other large impurity region and resistance value of surface sheet by a method wherein impurity is ion-implanted from a microscopic opening, and Si is implanted from above it, then heat-treated so as to control junction depth and resistance value of the surface sheet. CONSTITUTION:A photo-resist pattern 1 is formed on the surface of a silicon substrate containing boron (100) as a diffusion mask. The resist pattern 1 is formed with positive type resist, and a miniature opening 2 of 0.9mumX0.9mum and a contrast opening 3 of 3mumX3mum are formed with photo-etching method. After phosphor is ion-implanted, and the contrast opening 3 on the resist pattern 1 is covered with a mask, Si is ion-implanted into the silicon substrate through the miniature opening 3. Then, the previously ion-implanted impurity is diffused with heat-treatment to form a junction on the silicon substrate under the miniature opening 2 and the contrast opening 3, making it possible to the same junction depth as that of the junction with regular dimension and the surface sheet resistance.
|
