Semiconductor apparatus with variable resistor having tapered double-layered sidewall spacers and method for fabricating the same

摘要

A method for fabricating a semiconductor apparatus includes forming a variable resistor region, and forming a spacer having a top linewidth and a bottom linewidth substantially equal to each other in the variable resistor region. The forming of the spacer includes forming a first insulating layer in the variable resistor region through a first method, forming a second insulating layer along a surface of the first insulating layer in the variable resistor region through a second method for providing step coverage superior to the first method, and etching the first and second insulating layers.

主权项

1. A method for fabricating a semiconductor apparatus, the method comprising:
forming a lower electrode on a semiconductor substrate; forming an interlayer insulating layer on the semiconductor substrate; etching the interlayer insulating layer thus exposing an upper surface of the lower electrode, thereby forming a variable resistor region; non-conformally forming a first insulating layer along the interlayer insulating layer and the exposed lower electrode using a PVD (physical vapor deposition) method; conformally forming a second insulating layer over a surface of the first insulating layer using a CVD (chemical vapor deposition) or an ALD (atomic layer deposition); etching the first and the second insulating layers, thereby forming a spacer in the variable resistor region; forming a variable resistor device, which is in contact with the lower electrode, in the variable resistor region in which the spacer is formed; and forming an upper electrode over the variable resistor device to be coupled to the variable resistor device.