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Process Compact Modelling of Strain-Engineered MOSFETs
Other important features of the process-aware SPICE model are that it is
measurable, adjustable, and statistically independent, can be monitored and
recorded as part of an ongoing manufacturing process, allows desensitisation of design to process variations and design-specific process centring,
and enables engineers to consistently optimise the process and design with
minimal experimental efforts, which results in significant productivity
improvements.
Process-aware design for manufacturing involves analyses of variability
effects at the custom/analogue design stage that enable the designers to
see how much they can push the design rules and realise the full potential
of technology scaling. The process-dependent SPICE models allow direct
access to process parameter variations in circuit design [6]. For example,
change of the gate length results in change of the device parasitic, which
can be included in timing analysis by the circuit designer for examining
the delays leading to variation-aware circuit design. The use of PCM significantly improves design for manufacturing (DFM) by allowing for accurate
design sensitivity analysis and parametric yield assessment, as a function of
statistically independent and measurable process variations.
9.4 Process Compact Model
In the following, we present a simulation methodology for strain-engineered
MOSFETs that allow the flow of pertinent information between process
and design engineers without the need for disclosing the detail of process
technology. Compact SPICE model parameters are obtained using parameter extraction strategy by using a polynomial function of process parameter variations. A strategy to acquire compact SPICE model cards has been
developed. As a case study, SPICE models are used to identify the impacts
of process variability on the performance of inverter circuits with strainengineered MOSFETs.
Technology CAD (TCAD) is a powerful tool to identify the root causes
for yield loss and is used to study device sensitivities on process variations.
Currently, TCAD is heavily used in device research and process integration
phases of technology development. However, a major trend in the industry
is to apply TCAD tools far beyond the integration phase into manufacturing and yield optimisation. Linking of process parameter variations (via
design of experiments) with the electrical parameters of a device through
a process compact model (PCM) is discussed. Application of stable and
well-calibrated TCAD tools as an aid for manufacturing of process-induced
strain-engineered CMOS is described.
Toward extended TCAD, in process modelling, generally a systematic
design of experiments (DoE) run is performed. DoE experimentation is
Process Compact Modelling of Strain-Engineered MOSFETs
Other important features of the process-aware SPICE model are that it is
measurable, adjustable, and statistically independent, can be monitored and
recorded as part of an ongoing manufacturing process, allows desensitisation of design to process variations and design-specific process centring,
and enables engineers to consistently optimise the process and design with
minimal experimental efforts, which results in significant productivity
improvements.
Process-aware design for manufacturing involves analyses of variability
effects at the custom/analogue design stage that enable the designers to
see how much they can push the design rules and realise the full potential
of technology scaling. The process-dependent SPICE models allow direct
access to process parameter variations in circuit design [6]. For example,
change of the gate length results in change of the device parasitic, which
can be included in timing analysis by the circuit designer for examining
the delays leading to variation-aware circuit design. The use of PCM significantly improves design for manufacturing (DFM) by allowing for accurate
design sensitivity analysis and parametric yield assessment, as a function of
statistically independent and measurable process variations.
9.4 Process Compact Model
In the following, we present a simulation methodology for strain-engineered
MOSFETs that allow the flow of pertinent information between process
and design engineers without the need for disclosing the detail of process
technology. Compact SPICE model parameters are obtained using parameter extraction strategy by using a polynomial function of process parameter variations. A strategy to acquire compact SPICE model cards has been
developed. As a case study, SPICE models are used to identify the impacts
of process variability on the performance of inverter circuits with strainengineered MOSFETs.
Technology CAD (TCAD) is a powerful tool to identify the root causes
for yield loss and is used to study device sensitivities on process variations.
Currently, TCAD is heavily used in device research and process integration
phases of technology development. However, a major trend in the industry
is to apply TCAD tools far beyond the integration phase into manufacturing and yield optimisation. Linking of process parameter variations (via
design of experiments) with the electrical parameters of a device through
a process compact model (PCM) is discussed. Application of stable and
well-calibrated TCAD tools as an aid for manufacturing of process-induced
strain-engineered CMOS is described.
Toward extended TCAD, in process modelling, generally a systematic
design of experiments (DoE) run is performed. DoE experimentation is