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2.830J / 6.780J / ESD.63J Control of Manufacturing Processes (SMA 6303) Spring 2008

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Control of Manufacturing

Processes

Subject 2.830/6.780/ESD.63 Spring 2008 Lecture #2

Semiconductor Process Variation

February 7, 2008

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http:2.830/6.780/ESD.63

Agenda The Semiconductor Fabrication Process

Manufacturing process control

Types of Variation in Microfabrication Defects vs. parametric variations Temporal variations: wafer to wafer (run to run)

Spatial variations: wafer, chip, and feature level

Preview of manufacturing control techniques Statistical detection/analysis of variations Characterization/modeling of processes & variation Process optimization & robust design Feedback control of process variation

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Semiconductor Fabrication Process, Part 1

R. J. Shutz, in Statistical Case Studies for Industrial Process Improvement, pp. 470-471, SIAM, 1997.Manufacturing Courtesy of the Society for Industrial and Applied Mathematics. Used with permission.

3

Semiconductor Fabrication Process, Part 2

R. J. Shutz, in Statistical Case Studies for Industrial Process Improvement, pp. 470-471, SIAM, 1997.Manufacturing Courtesy of the Society for Industrial and Applied Mathematics. Used with permission.

4

Semiconductor Fabrication Process, Part 3

R. J. Shutz, in Statistical Case Studies for Industrial Process Improvement, pp. 470-471, SIAM, 1997.Manufacturing Courtesy of the Society for Industrial and Applied Mathematics. Used with permission.

5

Semiconductor Fabrication Process, Part 4

R. J. Shutz, in Statistical Case Studies for Industrial Process Improvement, pp. 470-471, SIAM, 1997.Manufacturing Courtesy of the Society for Industrial and Applied Mathematics. Used with permission.

6

(Semiconductor) Manufacturing

Process Control

Image removed due to copyright restrictions. Please see Fig. 26 in Boning, D. S., et al. A General Semiconductor Process Modeling Framework. IEEE Transactions on Semiconductor Manufacturing 5 (November 1992): 266-280.

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Agenda The Semiconductor Fabrication Process

Manufacturing process control

Types of Variation in Microfabrication Defects vs. parametric variations Temporal variations: wafer to wafer (run to run)

Spatial variations: wafer, chip, and feature level

Preview of manufacturing control techniques Statistical detection/analysis of variations Characterization/modeling of processes & variation Process optimization & robust design Feedback control of process variation

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Defect vs. Parametric Variation

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Yield & Variation from Defects Electrical test

measure shorts in test

structures for different spacings between patterned lines (at or

near the design rule or DR

feature size)

measure opens in other test

structures

Images removed due to copyright restrictions. Please see: Hess, Christopher. "Test Structures for Circuit Yield Assessment and Modeling." IEEE International Symposium on Quality Electronics Design, 2003.

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Temporal Variation

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Spatial Variation

Wafer scale Chip scale Feature scale

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Modeling of Processes

and Variation

Empirical modeling Physical modeling

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Process Optimization & Robust Design

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Image removed due to copyright restrictions. Please see Fig. 7 in Lakshminarayanan, S., et al. Design Rule Methodology to Improve the Manufacturability of the Copper CMP Process. Proceedings of the IEEE International Interconnect Technology Conference (2002): 99-101.

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Feedback Control of Variation

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EQUIPMENT MATERIALCONTROLLER

The General Process Control Problem Desired

MATERIAL ProductProduct

EQUIPMENTCONTROLLER

Equipment loop

Material loop

Process output loop

Control of Equipment:

Forces,

Velocities

Temperatures, ...

Control of Material

Strains

Stresses

Temperatures,

Pressures, ...

Control of Product:

Geometry

and

Properties

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Summary The Semiconductor Fabrication Process

Manufacturing process control

Types of Variation in Microfabrication Defects vs. parametric variations Temporal variations: wafer to wafer (run to run)

Spatial variations: wafer, chip, and feature level

Preview of manufacturing control techniques Statistical detection/analysis of variations Characterization/modeling of processes & variation Process optimization & robust design Feedback control of process variation

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Control of Manufacturing ProcessesAgenda(Semiconductor) Manufacturing Process ControlAgendaDefect vs. Parametric VariationYield & Variation from DefectsTemporal VariationSpatial VariationModeling of Processes and VariationProcess Optimization & Robust DesignFeedback Control of VariationThe General Process Control ProblemSummary