Ruiqi Tian
ABSTRACT
Manufacturability of a design that is processed with shallow trench isolation (STI) depends on the uniformity of the chemical-mechanical polishing (CMP) step in STI. The CMP step in STI is a dual-material polish, for which all previous studies on dummy feature placement for single-material polish [3, 11, 1] are not applicable. Based on recent semi-physical models of polish pad bending [5], local polish pad compression [2, 10], and different polish rates for materials present in a dual-material polish [2, 13], this paper derives a time-dependent relation between post-CMP topography and layout pattern density for CMP in STI. Using the dependencies derived, the first formulation of dummy feature placement for CMP in STI is given as a nonlinear programming problem. An iterative approach is proposed to solve the dummy feature placement problem. Computational experience on four layouts from Motorola is given.
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Index Terms
- Dummy feature placement for chemical-mechanical polishing uniformity in a shallow trench isolation process
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Model-based dummy feature placement for oxide chemical-mechanical polishing manufacturability
DAC '00: Proceedings of the 37th Annual Design Automation ConferenceChemical-mechanical polishing (CMP) is an enabling technique used in deep-submicron VLSI manufacturing to achieve uniformity in long range oxide planarization [1]. Post-CMP oxide topography is highly related to local spatial pattern density in layout. ...
Dummy-feature placement for chemical-mechanical polishing uniformity in a shallow-trench isolation process
Manufacturability of a design that is processed with shallow-trench isolation (STI) depends on the uniformity of the chemical-mechanical polishing (CMP) step in STI. The CMP step in STI is a dual-material polish for which all previous studies on dummy-...
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