Patent ID: 6942732
Filing Date: 2005-09-13
Classification: H01L

Abstract:
1. A method for forming a double density wordline, comprising: providing a semiconductor substrate; sequentially forming a poly layer, a first insulating layer, a first sacrificial layer, a second insulating layer, and a photoresist layer with a wordline pattern on the semiconductor substrate; sequentially etching the second insulating layer and the first sacrificial layer using the photoresist layer as an etching mask until the first insulating layer is exposed to form a first wordline mask, a second wordline mask, and an opening therebetween; removing the photoresist layer; forming a spacer on a sidewall of the opening; forming a second sacrificial layer in the opening; removing the spacer, the second insulating layer, and the first insulating layer under the spacer to form a third wordline mask composed of the second sacrificial layer and the first insulating layer thereunder; and etching the poly layer to form a first wordline, a second wordline, and a third wordline using the first wordline mask, the second wordline mask, and the third wordline mask as etching masks.