Dual damascene trench depth monitoring
AssigneeAdvanced Micro Devices, Inc.
InventorsRamkumar Subramanian, Christopher F. Lyons
Life of this patent
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Abstract
One aspect of the present invention relates to a method of dual damascene processing, involving forming a plurality of via openings in the insulation structure containing a single layer of a dielectric material; and simultaneously (i) forming a plurality of trenches in the insulation structure, each trench positioned along the substantially straight line of a group of via openings, and (ii) monitoring the formation of trenches using a scatterometry system to determine trench depth, and terminating forming the trenches when a desired trench depth is attained.
Claims20
A method of dual damascene processing, comprising:
- providing a semiconductor substrate with an insulation structure on an upper surface thereof, the insulation structure consisting essentially of a single layer of a dielectric material;
- forming a plurality of via openings in the insulation structure, wherein groups of via openings are positioned in a substantially straight line;
- simultaneously
- (i) forming a plurality of trenches in the insulation structure, each trench positioned along the substantially straight line of a group of via openings, and
- (ii) monitoring the formation of trenches using a scatterometry system by generating a signature associated with forming the trenches, comparing the signature to a signature library to determine trench depth, and terminating forming the trenches when a desired trench depth is attained;
- and
- filling the trenches and via openings with a conductive metal.
A method of forming a dual damascene opening in a semiconductor substrate, comprising:
- providing a semiconductor substrate with an insulation structure on an upper surface thereof, the insulation structure consisting essentially of a single layer of a dielectric material;
- forming at least one via opening in the insulation structure;
- and
- simultaneously
- (i) forming a trench in the insulation structure, the trench positioned above the via opening, both the via opening and the trench constituting the dual damascene opening, and
- (ii) monitoring forming the trench using a scatterometry system by:
- directing a beam of incident light at the insulation structure,
- collecting light reflected from the insulation structure,
- transforming the reflected light into a signature associated with forming the trench,
- comparing the signature to a signature library to determine trench depth, and
- terminating forming the trench when a desired trench depth is attained.
A method of forming a dual damascene structure, comprising:
- providing a semiconductor substrate with an insulation structure on an upper surface thereof, the insulation structure consisting essentially of a single layer of a dielectric material;
- forming a plurality of via openings in the insulation structure, wherein groups of via openings are positioned in a substantially straight line;
- simultaneously
- (i) forming a plurality of trenches in the insulation structure using a trench etch controller, each trench positioned along the substantially straight line of a group of via openings, and
- (ii) monitoring the formation of trenches using a scatterometry system by generating a signature associated with forming the trenches, comparing the signature to a signature library to determine trench depth, and
- if the determine trench depth is not within an acceptable range of desired trench depths, instructing the trench etch controller to continue forming the trenches and optionally adjust a trench etch process component;
- if the determine trench depth is within an acceptable range of desired trench depths, instructing the trench etch controller to terminate forming the trenches;
- and
- filling the trenches and via openings with a conductive metal.
Dependencies are inferred from the claim text.