摘要 |
The present invention provides a method for forming a flash memory cell and comprises following steps. First, a substrate is provided. Then, a gate dielectric layer, a first polysilicon layer and a hard mask layer are sequentially formed on the substrate. Next, a portion of the hard mask layer, the polysilicon layer, and the gate dielectric layer are removed to form a plurality of holes to expose the substrate. Following, a dielectric layer is formed in those holes by a HDPCVD process. Last, the hard mask layer on the first polysilicon layer is removed by the HDPCVD process. Further, a second polysilicon layer could be conformally formed on the first polysilicon layer and the isolation dielectric.
|