Alternating phase shift mask
AssigneeSeagate Technology LLC
InventorsDan Yu, Aaron Michael Bowser
Life of this patent
Estimating the term…
Abstract
An alternating phase-shifting mask (Alt-PSM) comprising a 0° phase portion having a first width and a 180° phase portion having a second width greater than the first width. Example differences between the width of the 180° phase portion and the 0° phase portion may be 10 nm, 15 nm, or 20 nm. An Alt-PSM having phase portions of different widths can have an aerial image intensity transmission graph that is symmetric, for example, at 0.2-0.3 intensity.
Claims20
A method of forming an individual feature on a wafer using a photolithography process, the method comprising:
- providing an alternating phase-shifting mask (Alt-PSM) comprising a 0° phase portion having a first width and a 180° phase portion having a second width less than 1 micrometer and greater than the first width, the 0° phase portion adjacent to the 180° phase portion at a phase transition edge,
- forming the individual feature on the wafer using the Alt-PSM via the photolithography process, the feature formed on the wafer at a location aligned with the phase transition edge of the Alt-PSM, the feature having a dimension less than 150 nm.
A method of forming an individual feature on a wafer, the method comprising:
- providing an alternating phase-shifting mask (Alt-PSM) comprising a 0° phase portion having a first width and a 180° phase portion having a second width less than 1 micrometer and greater than the first width, the 0° phase portion adjacent to the 180° phase portion at a phase transition edge,
- transmitting light through the Alt-PSM onto the wafer to form the individual feature on the wafer at a location corresponding to the phase transition edge, the feature having a dimension less than 150 nm.
A method of creating an aerial image intensity graph, the method comprising:
- providing an alternating phase-shifting mask (Alt-PSM) comprising a 0° phase portion having a first width and a 180° phase portion having a second width less than 1 micrometer and greater than the first width, the 0° phase portion adjacent to the 180° phase portion at a phase transition edge;
- and
- creating the aerial image intensity graph by transmitting light through the Alt-PSM and recording an intensity of the transmitted light, the graph showing no transmission intensity through the Alt-PSM at the phase transition edge and symmetrical transmission intensity at 0.2-0.3 intensity through the 0° phase portion and the 180° phase portion.
Dependencies are inferred from the claim text.