| 摘要 |
PROBLEM TO BE SOLVED: To improve the uniformity of concentration of phosphorus in the depthwise direction of a film, by increasing a PH3 gas flow to increase the concentration of phosphorus and, after a lapse of given time, decreasing the PH3 gas flow to a set flow. SOLUTION: A field oxide film 102 and a gate oxide film are formed on a p-type silicon substrate 101, a gate electrode is formed thereon, a diffusion layer 104 for a capacitor and a diffusion layer 105 far a bit line are formed thereon, an insulating film 106 is deposited thereon, then a bit line 107 and an insulating film 108 are deposited thereon, and a contact hole 109 for exposing the n-type diffusion layers 104, 105 is made. Thereafter, an amorphous silicon film 110a doped with phosphorus is formed by flowing a PH3 gas at a flow of 60-70 sccm and, after a lapse of given time, a SiH4 gas is flowed at a flow of 1600 sccm to deposit a silicon film 110c doped with phosphorus to form a stack capacitor electrode 112. After a natural oxide film is removed, the stack capacitor electrode 112 is subjected to HSG to form dips and bumps on its surface. Therefore, this can greatly inhibit a short circuit made by silicon migration when an HSG electrode is formed. |
