Micromachining of Silicon Micromachining of Silicon and and

Its Applications in MEMS and Its Applications in MEMS and Intelligent SensorsIntelligent Sensors

Mustafa G. Guvench, Ph.D.Mustafa G. Guvench, Ph.D.

University of Southern MaineUniversity of Southern Maine

What is MICRO-MACHINING?

What is MICRO-MACHINING?

What is MICRO-MACHINING?

What is MICRO-MACHINING?

What can Micromachined Parts/Systems do for us?

Be a Conduit to Microscopic Domain:

1. Sensing (Information)2. Information Processing 3. Communication4. Manipulation (Actuation and Control)

Why / Why not

SILICON?

Semiconductor: Semiconductor: Active Devices + SensorsActive Devices + Sensors(Photo-Magneto-Strain Sensing)(Photo-Magneto-Strain Sensing)

Insulator:Insulator: SiOSiO22 , Si , Si33NN44 , Glass , Glass

Thin Film Conductor:Thin Film Conductor: Aluminum, Gold, SilicidesAluminum, Gold, Silicides

PhotoLithography:PhotoLithography: Planar control (+ & -)Planar control (+ & -)

Mechanical Material

SILICON?

Stiff => Stiff => Thinning is required for appreciable strainThinning is required for appreciable strain

Micromachining of

SILICON?

MICROMACHINING of SILICON => MICROMACHINING of SILICON => (a) (a) BULK (substrate)BULK (substrate)(b) (b) SURFACE (films)SURFACE (films)

Additive Processes: Additive Processes: Chemical and Physical DepositionChemical and Physical Deposition(Thin Layers only) (Single/Poly)(Thin Layers only) (Single/Poly)

Removal Processes:Removal Processes: Chemical and Physical EtchingChemical and Physical Etching(Wet/Dry/Plasma/Inert/Reactive)(Wet/Dry/Plasma/Inert/Reactive)

(Bulk/Film) (Anisotropic/Isotropic)(Bulk/Film) (Anisotropic/Isotropic)

BULK MICROMACHINING(Etchants: Isotropic/Anisotropic)

BULK MICROMACHINING(Isotropic/Anisotropic)

BULK MICROMACHINING(Cavity/Cantilever Anisotropic)

BULK MICROMACHINED(Silicon Capillary for Insulin Infuser)

BULK MICROMACHINED(Silicon Capillary for Insulin Infuser)

BULK MICROMACHINED(Silicon Capillary for Insulin Infuser)

BULK MICROMACHINED(Silicon Mask for Cylindrical Micromotion Sensor)

BULK MICROMACHINED(Series Connected Photovoltaic Converter Battery)

BULK MICROMACHINED(Series Connected Photovoltaic Converter Battery)

BULK MICROMACHINED(Series Connected Photovoltaic Converter Battery)

MOTION? HANDLING? ASSEMBLY?COUPLING? =>

MicroElectroMechanicalSytems

M (CMOS-IC Technology) + E (CMOS-IC Technology) +

M (Silicon and Sacrificial Layers) +

O (Aluminum) +

S (IC Packaging Technology)

Three-Layer Poly-Silicon Surface Micromachining Process

(to build Mechanical Parts on CMOS IC)

Final cross sectional view with 7 layersFinal cross sectional view with 7 layers

Three-Layer Poly-Silicon Surface Micromachining Process

Surface Micromachined

Micromachining of Projection Camera

M (CMOS-IC Technology) + E (CMOS-IC Technology) +

M (Silicon and Sacrificial Layers) +

O (Aluminum) +

S (IC Packaging Technology)

M.G.GuvenchM.G.Guvench

Surface Micromachined Silicon SensorsSurface Micromachined Silicon Sensors

M.G.GuvenchM.G.Guvench

Surface Micromachined Silicon SensorsSurface Micromachined Silicon Sensors

M.G.GuvenchM.G.Guvench

Electrostatic Field SensorsElectrostatic Field Sensors

M.G.GuvenchM.G.Guvench

Electrostatic Field SensorsElectrostatic Field Sensors

M.G.GuvenchM.G.Guvench

Electrostatic Field SensorsElectrostatic Field Sensors

M.G.GuvenchM.G.Guvench

Mass (Absorption/Deposition) SensorMass (Absorption/Deposition) Sensor

M.G.GuvenchM.G.Guvench

Mass (Absorption/Deposition) SensorMass (Absorption/Deposition) Sensor

M.G.GuvenchM.G.Guvench

Mass (Absorption/Deposition) SensorMass (Absorption/Deposition) Sensor

M.G.GuvenchM.G.Guvench

Electrostatic Field SensorsElectrostatic Field Sensors

M.G.GuvenchM.G.Guvench

Flow Skin Friction SensorsFlow Skin Friction Sensors

M.G.GuvenchM.G.Guvench

Flow Skin Friction SensorsFlow Skin Friction Sensors

M.G.GuvenchM.G.Guvench

CMOS Analog Chip Design (Operational Amplifier)CMOS Analog Chip Design (Operational Amplifier)

M.G.GuvenchM.G.Guvench

MicroFab Laboratory

Programmable Diffusion/Oxidation System’s Programmable Diffusion/Oxidation System’s Controller in The MicroFab LaboratoryController in The MicroFab Laboratory

Double-Diffused PDouble-Diffused P++NNNN++ Junction PhotoDiode Junction PhotoDiode Made Being Tested in The MicroFabrication Lab.Made Being Tested in The MicroFabrication Lab.

MicroFab Laboratory

Surface Micromachined Silicon SensorsSurface Micromachined Silicon Sensors

M.G.GuvenchM.G.Guvench

3-Poly Surface Micromachining ProcessedSensors

Cross SectionCross Section

MEMS Switch

MEMS MicromotorMEMS Micromotor

A Mass (Absorption/Deposition) SensorA Mass (Absorption/Deposition) Sensor

M.G.GuvenchM.G.Guvench