Lecture_2_MEMS_09 - MEMS/NEMS Materials and basic processes...

Info iconThis preview shows pages 1–29. Sign up to view the full content.

View Full Document Right Arrow Icon
MEMS/NEMS Materials and basic processes Laws of physics – scaling down Lecture #2
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Content of the lecture • Silicon as a electro-mechanical material • Design process of MEMS • Silicon technology • Deposition – patterning – removal cycle • Photolithography process
Background image of page 2
Silicon as a material
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The electric properties of doped Si
Background image of page 4
The electrical properties of Si • Atomic density : 5 10 22 atoms/cm 3 • Bandgap : E g = 1.11eV = 1.776 10 -19 J • Charge carrier concentration – Intrinsic Si : n = p = n i kT E p n i g e h T k m m n 2 / 3 2 2 2 * * 2 4 4 m n *, m p *, k, t, h E g are effective mass of electrons, holes, Boltzmann’s constant, Absolute temperature, Planck’s constant, bandgap
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The electrical properties of Si - 2 • Electron driven carriers : n(egative) type • Hole driven carrier – p(ositive) type • Extrinsic materials – semiconductors with impurities • Under thermal equilibrium, n o p o =n i 2
Background image of page 6
Fundamental advantage of fabrication on Si
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Silicon production
Background image of page 8
Silicon production
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The output
Background image of page 10
Silicon wafers
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Silicon wafers - 2
Background image of page 12
Silicon wafers - 2
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Clean room standards
Background image of page 14
Silicon crystallography
Background image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
How to produce MEMS – flowchart level
Background image of page 16
MEMS design methodology
Background image of page 17

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The design tools • Device design: – Cadence, L-Edit, MEMSPro • Process design: – TCAD (surf), AnisE (bulk) • Analysis/Synthesis: – MEMSCAD, MEMSPro, – FEA (Ansys, Nastran)
Background image of page 18
Main processes in semiconductor – lithography based process
Background image of page 19

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Deposition – addition process • Deposition of uniform deposited films • Films deposited from the solid target (vacuum associated with high energy dissipation) • Films deposited from liquid phase (electro- chemical deposition, spin coating, etc.) • Films deposited from gaseous phase – solid phase generated by a chemical reaction
Background image of page 20
Deposition principle • Compliant material covers the substrate
Background image of page 21

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Deposition principle - 2 • The approach angle plays an important role
Background image of page 22
Deposition from solid phase • Vacuum deposition – thermal energy - target is heated
Background image of page 23

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Deposition from solid phase - 2 V 2 V 3 V 1 , High Vac valve High Vacuum Pump Vacuum Chamber Roughing Pump
Background image of page 24
Deposition from solid phase - 3 • Chemical Vapor Deposition – ex. Tungsten
Background image of page 25

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Deposition from solid phase - 4
Background image of page 26
Deposition – Chemical Vapor Deposition (CVD)
Background image of page 27

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Deposition - Oxidation • Oxygen atmosphere causes Si to oxidize to its natural silicon dioxideSiO 2 • Si grows out of Si and reduces the thickness of the substrate •A thickness of 100 units removes out of Si ~ 45 units •Dry oxidation reaction: Si (solid) + O 2 (gas) -> SiO
Background image of page 28
Image of page 29
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/08/2010 for the course MECHANICAL 6537 taught by Professor Stiharu during the Winter '10 term at Concordia Canada.

Page1 / 77

Lecture_2_MEMS_09 - MEMS/NEMS Materials and basic processes...

This preview shows document pages 1 - 29. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online