| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing a semiconductor device by which the adsorption and diffusion of impurities to a part other than the specified part are prevented and the formation of parasitic transistor and short-circuit of a capacitor are also prevented. SOLUTION: A diffusion source material PSG is embedded from the groove bottom to the specified height in a groove 18 formed on the surface of a silicon semiconductor substrate 11, and further a silicon dioxide film 20 is formed as an insulation film on the upper surface of the PSG and on the inner surface of the groove 18 that is higher than it, and then the impurities from the PSG to an area adjacent to the groove of the board 11 are subject to diffusion through heating. Then, the silicon dioxide film 20 on the surface of the PSG is removed through anisotropic etching, and after the PSG is removed, a dielectric film 22 is formed on the inner surface of the groove 18 and an amorphous silicon 23 containing a phosphorus as conductive material is embedded inside the groove 18. Thus, no impurity evaporate from the upper surface of the PSG where the silicon dioxide film 20 is formed, while the impurities is diffused, and the impurities can be prevented from adsorption and diffusion to a part other than the specified part. |
