Patent ID: 7871934
Filing Date: 2011-01-18
Classification: H01L,Y10S

Abstract:
1. A method for forming a portion of a circuit comprising: forming a layer as part of the circuit in a device; forming a trough in the layer using an etch controlled by a first photoresist mask on the layer using a first set of etching parameters, the trough having a bottom and side walls forming a width dimension of the trough; and forming a contact hole under the trough using an etch controlled by a second photoresist mask applied to a portion of the circuit in the device free of alignment of the second photoresist mask to the width dimension of the trough, the second photoresist mask having a width dimension of an opening therein being larger than the width dimension of the trough so that the second photoresist mask is free of having a portion thereof from extending into a portion of the trough, and controlled by using an etch stop layer formed on a portion of the circuit in the device, the contact hole formed using a second set of etching parameters for use with a second photoresist mask.