Device and method for alignment of vertically stacked wafers and die
AssigneeSTMicroelectronics S.r.l.
InventorsJohn H. ZHANG, Walter KLEEMEIER, Paul FERREIRA, Ronald K. SAMPSON
Life of this patent
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Abstract
A device is provided that includes a first die having a first alignment structure that includes a plurality of first transmission columns arranged in a pattern and a second die positioned on the first die, the second die having a second alignment structure that includes a plurality of second transmission columns arranged in the same pattern as the first transmission columns. The first and second transmission columns are each coplanar with a first surface and a second surface of the first and second die, respectively.
Claims18
A method of aligning a plurality of die, comprising:
- positioning a first die having a first plurality of alignment structures overlying a second die having a second plurality of alignment structures, the first plurality of alignment structures having a first plurality of transmission columns arranged in a pattern and the second plurality of alignment structures having a second plurality of transmission columns arranged in the pattern of the first transmission columns;
- applying a first signal to the first plurality of alignment structures;
- detecting a second signal at the second plurality of alignment structures;
- determining a difference between the first and second signals;
- and
- adjusting a position of the first die with respect to the second die to decrease the difference between the first and second signals.
A method, comprising:
- forming a plurality of first transmission columns in a first wafer, the first transmission columns arranged in a pattern;
- forming a plurality of second transmission columns in a second wafer, the second transmission columns arranged in the pattern;
- aligning the first wafer with the second wafer by matching the pattern of the first wafer with the pattern of the second wafer, the aligning including:
- applying a signal to the first transmission columns;
- detecting the signal at the second transmission columns;
- and
- adjusting a position of the first wafer with respect to the second wafer to more precisely align the pattern.
A method, comprising:
- positioning a plurality of first capacitive alignment structures on a first die in close proximity to a plurality of second capacitive alignment structures on a second die;
- detecting a first capacitance between at least one of the plurality of first capacitive alignment structures and at least one of the plurality of second capacitive alignment structures;
- adjusting a position of the first die with respect to the second die;
- detecting a second capacitance between the at least one of the plurality of first capacitive alignment structures and the at least one of the plurality of second capacitive alignment structures;
- comparing the first capacitance to the second capacitance;
- and
- precisely aligning the first die with the second die by adjusting the position of the first die with respect to the second die based on the comparing.
Dependencies are inferred from the claim text.