Project Description & Process...

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Project Description & Process Flow

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Flow cytometry is an important bioanalytical technique that is used for sorting and counting of cells, measurements of physical and chemical characteristics of cells etc.

Flow Cytometry

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang

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Flow Cytometer /Molecular Focusing on a Chip

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang

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Hydrodynamic Focusing and Electrokinetic Focusing

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang

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Optical Waveguide on a Chip Optical waveguides are widely used, especially in the form of optical fibers, for long distance, high data rate telecommunications.

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang

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Thin Film Deposition

Oxidization

Photolithography

Etching

Ion Implantation / Diffusion

Packaging

Basic Microfabrication Steps

CMOS

bipolar

Optical-MEMS

Bio-MEMS

etc.

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang

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• Dry Oxidization : Si (solid) + O2 (gas) à SiO2 (solid) • Wet Oxidization: Si (solid) + 2H2O (gas) à SiO2 (solid) + 2H2 (gas)

Thermal Oxidization

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang

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Photolithography

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang

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Etching

•  Wet etch vs Dry Etch

•  Etch Selectivity

•  Etch Rate

•  Degree of Anisotropy

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Thin Film Deposition : Evaporation

  Focused beam of electrons are used to locally heat the source

  Can be used to heat/evaporate even high melting point materials

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang

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Packaging: Anodic Bonding

•  High voltage (300 -1000 V) generates large electrostatic forces

•  High temperature (300-600 C) facilitates bonding •  Bonds SiO2 to Si or metal

•  Use Pyrex 7740 or Borofloat glass to match thermal expansion coefficient

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang

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Layout of Flow Cytometer (FC)

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang

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Process Flow for Flow Cytometer (FC)

(positive PR)

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang

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Process Flow for Flow Cytometer (FC)

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang

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SU-8 is negative PR

520/530/580.495 Fall 2015 A.G. Andreou and T.H. Wang