对氧化后硅片上的多晶硅膜,进行了砷离子注入前的快速热处理退火。离子注入之后,这种膜进行了另外的快速热处理退火以活化砷。注入前退火使得刚淀积的晶粒尺寸增大到10倍。这些膜的薄层电阻比只是注入后进行退火处理的膜的要低20～30％。注入前退火引起的晶粒尺寸增大,使得晶粒边界区域减小,从而使相对于晶粒的晶粒边界中掺杂剂数量减少至最低限度。 The polycrystalline silicon film on the oxidized silicon wafer is subjected to a rapid thermal annealing before arsenic ion implantation. After ion implantation, this film was subjected to another rapid thermal annealing to activate arsenic. Annealing before injection increased the size of freshly deposited grains by a factor of 10. The sheet resistance of these films is 20 to 30% lower than that of an annealed film only after injection. Increasing the grain size due to the pre-injection annealing causes the grain boundary region to decrease, thereby reducing the amount of dopant in the grain boundaries relative to the grains to a minimum.