MAI Lab

1
??? ?? ??
2002 . 8 . 16
MAI Lab
? ? ?
MAI Lab Seminar
2
Contents
1. ??? ?? ?? (Overview)
2. ????? ??
3. ?? ?? ? ??
4. ?? ? ??
MAI Lab Seminar
3

• ??? ?? ??

MAI Lab Seminar
4
Overview
Logic Design
Wafer Preparation
Circuit Design
Mask(Reticle)
Wafer Fabrication
Assembly
Test
5
Overview
FAB ??
Logic ? ?? ??
Mask ??
??? ??
??? ?? ??
??? ??
6
Overview
Oxidation
PR ??
Exposure
Development
Etching
?? ??
Metallization
CVD
Ion ??
7
Overview
Test ? ??
Sawing
Chip ??
Wire bonding
molding
Final test
8
2. ????? ??
MAI Lab Seminar
9
Wafer Preparation

• ???? ??
• Dopant ??? ??
•    -  N-Type 5? ??(P, Sb) ? Dopant? ??, ???? ??
  
•    -  P-Type 3? ??(B) ? Dopant? ??, Hole(??) ??
  
• ???? ??? ??
•    -  100
•    -  111
• ???? ??? ??
•    -  3??, 4??, 5??, 6??(150mm), 8??(200mm),
  12??(300mm)

10
Wafer Preparation
donor
n-type
acceptor
p-type
11
Wafer Preparation
Crystal Growing
???, ?? ??, ???, ?? ??
Slicing
???/???, ???, ???
Cleaning
Edge Profiling
???, ???
Lapping
???/???, ???, ???, ???
Laser Marking
Cleaning
Etching
Cleaning
Heat Treatment
Cleaning
Polishing
???, ???, Damage, ???
Cleaning
Inspection
Packing
12
Wafer Preparation
Preparation
Melting
Body growth
Cool-down Ingot removal
Evaluation
13
Wafer Preparation
Slicing
Lapping
Etching
Heat Treatment
Polishing
14
Wafer Preparation
Epitaxial Processing
Cleaning
Inspection
Packing
15
Wafer Preparation
Crystal Growing
Czochralski Method (CZ)
Floating Zone Method (FZ)
16
Wafer Preparation
CZ?? ?? silicon ??? ?? ??
Stacking
??? ??? ?? (Crucible Size, ??? ?)
Pump-Down
??? ? ??? (Final Pressure, Leak Rate)
Melting
?? ? ?? (inert gas flow rate, crucible ???)
Dipping
??? ???? ?? (?? ??, Seed/crucible ???)
Necking
???? ?? ???? ?? (Neck ??/??, ????)
Shouldering
Neck???? ?????? ?? (???? ? ?? ??)
Body Growth
??? ??? ?????? ?? (????, ???)
Tailing
???? ?? ???? ?? (?? tail ??, ?? ??)
Cool-Down
???? ?? (?? ??/??)
17
Wafer Preparation
grinding   ??? ??? ??? ??? ??? ??? ?? ??? ????,
??? ?? ??? ???? ??? ?? ????? ???? ????.
slicing   ???? ?????? ???? ????. ??? ???? ????
??? ??? ??? ??? ?? ???? ??? ?? ?? ??? ???? ??.
????? ?? ????? ??? ???? ???? ?? ???? ????.
18
Wafer Preparation
lapping   ??? ???? ?? ??? ???? ? ??? ???? ????
??? ?? ???? ???? ??? ??? ????. ????? ????? Al2O3
? ????(glycerine)? ?? ???? ??? ????? ?? ??? ????
????.
rounding   ???? ???? ?? ???? ??? ???? ?? ????
???? ???? ??? ????? ??? ??? ?? ???? ?? ?? ?????
?? powder? ????.
19
Wafer Preparation
etching   ? ????? ??? ???? ???? ???? ???? ????
?? ????? ?? ??. ?????? HF-HNO3-CH3 COOH ?? ???
????? ????.
polishing   ??? ???? ???? ?? ??? ????? ???? ???
??? ??? ?? CMP? ??. ???? ?? ??? ?? ??? ???? ??
???? ??? ??? ???? ????. ??? ????, ??? ?? ????
???? ??? ?????? ????.
20
Wafer Preparation

• Wafer-related Issues
• Wafer Geometry
• ? Flatness, Alignment, Distortion
• Wafer Cleanliness
• ? Defect Density Reduction, Particle Size
  Consideration
• Surface Chemistry Defects
• ? Oxidation, Metals, Cleaning
• Crystal Defects
• ? Stacking Faults, Dopant Uniformity, Metal
  Contamination

21
Lithography
Pattern Preparation
Photoresist Coating
Stepper Exposure
Develop Bake
Acid Etch
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Lithography
Positive Resist
SiO2
Resist
SiO2
SiO2
Si
Si
Si
Negative Resist
SiO2
Mask
SiO2
SiO2
Si
Si
Si
23
Lithography
Lithographic masking steps to produce Transistor
24
Lithography
Resist Processing
Coating Parameter

• Spin speed time

• Dispense volume

• Resist temperature

• Acceleration speed

• Viscosity

• Exhaust conditions

25
Lithography
Classification

• Exposing area solubility

- Positive Negative

• Wavelength

- g-line (436nm)
?? ???
- i-line (365nm)
- KrF (248nm)
Laser type
- ArF (193nm)
26
Lithography
Pattern Preparation

• Reticle? ?? ??? 1 10 ?

• Laser Pattern Generator

• E-Beam Pattern Generator

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Lithography
Proximity Contact Lithography
Projection Lithography
illumination light
Condensor lens
illumination light
Mask pattern
mask pattern
Diffracted light
gap
Projection lens
photoresist
q
wafer
Photoresist
Wafer
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Lithography
Conventional mask
PSM(Phase Shift Mask)
E-field at mask
E-field at wafer
Intensity at wafer
phase edge PSM
Alternating PSM
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Lithography
Next Generation of Lithography Technology

• X-Ray Lithography

Resolution ???, ?? ?? ??
Resolution ??? throughput ?? ??

• E-Beam Directing Lithography

E-beam Mask

• SCALPEL Lithography

Throughput, resolution ???, Mirror ??? ??? (???
?? ??)

• EUV Lithography

??? ?? ??

• Ion Beam Lithography

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Lithography
E-Beam Directing Writing Lithography
Electron source
Illumination lens
1st aperture
Beam blanker
Condensor lens
2nd aperture Cell mask
Beam Deflector
Objective lens
Wafer stage
Very Low throughput issue
31
Lithography
Key Technologies of Optical Lithography
32
Film Deposition
Deposition Source

• Heat

• Plasma

• hv (??)

For What ?

• Dielectrics

• Metal

Definition

• CVD Chemical Vapor Deposition

• ALD Atomic Layer Deposition

• High-k High Dielectric Constant

• Low-k Low Dielectric Constant

• PVD Physical Vapor Deposition (Sputter)

33
Film Deposition
CVD Model
PVD Model
ALD Model
34
Film Deposition
Deposition Application

• STI (Shallow Trench Isolation)
• ? Junction Isolation

• Gate Diode Tune On/Off

• PMD (Pre Metallization Dielectric)
• ? Wire Cap. Str. Support

• MC (Metal Contact)
• ? Power Supply to Tr Cap.

• IMD (Inter Metal Dielectric)
• ? Wire Support

• Passivation Protect Structure

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Film Deposition
High-k Material

• Gate

• Ultrathin SiO2

• Dielectric constant gt 15

• Capacitor

• Reduce Capacitor Height

• High Cell Capacitance

Low-k Material

• Decrease RC Delay

• Low Power Consumption

• ?? ?? ?? ? ????

• Reduce Cross-Talk Noise

• Reduce the Number of Metal Layer

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Metallization

• Metallization Metal interconnection
• Requirements of Interconnect Materials
• low resistivity
• resistance to electromigration
• good adhesion to adjacent layers
• stability of mechanical and electrical
  properties
• corrosion resistance
• non contaminants to device and equipment
• controllable deposition and patterning methods

37
Metallization
MC and Via Structure on Device
38
Metallization
Schematic Diagram of Process Feature in DRAM
39
Metallization
Schematic Diagram of Process Feature in Logic
Device
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Metallization
Metal Deposition Technology
41
Metallization
Schematic Diagram of Sputtering
42
Metallization
Schematic Diagram of CVD Chamber
43
Metallization
Two Step Al Application (Cold/Hot Deposition)
44
Metallization
CVD W Applications
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Metallization
Cu Interconnection

• Very Low Resistivity

• Good Electromigration Stressmigration

• Fast Diffusion in Si Dielectric

? Need Diffusion Barrier

• Oxidation Corrosion

• Etching Problem (dry etching ???)

? CMP, Damascene ?? ?
46
Metallization
Process Sequence of Cu Dual-Damascene
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Cleaning CMP
What is Cleaning ?

• Definition removing of unwanted materials or
• contaminants from wafer
  surfaces

• Wafer cleaning steps are the most widely used
  and
• repeated process steps in manufacturing.

• Increased chip density requires more wafer
  cleaning
• steps.

Typical Defects

• Bridges

• Gate oxide ??

• Photo Masking

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Cleaning CMP
Requirements for Ultraclean Wafer Surface

• Particle Free

• Metallic Contamination Free

• Organic Contamination Free

• Moisture Molecule Free

• Native Oxide Free

• Surface Microroughness Free

• Charge-Up Free

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Cleaning CMP
General Cleaning Method
Wet Cleaning
Dip
?? ?? ??? ??
Spray
???? wafer? chemical ?? Compact, Safe, Low cost
Chemical? vapor ??
Dry Cleaning
Vapor
Gas? UV? ???? ??? ?? ??
UV excited
Plasma? ???? radical, ??? gas ?? ? ??
Plasma
Brush Cleaning
Roll Brush
????? Post-CMP ??? ?? ?? Particle ??? ??
Spin Scrubbing
?? CVD, Metal Depo ? ??? ??
50
Cleaning CMP
What is CMP ?

• Definition
• - Chemical Mechanical Polishing
• - ???? ??? ???? ?? ???? ??? ???
• ???? ???? ??
• CMP? ????
• - wafer carrier, polishing pad, slurry

51
Cleaning CMP
CMP? ??? STI ?? ??
Stacked via?? W Etch back? CMP ??? ??
W Etch Back
W CMP
52
3. ?? ?? ? ??
MAI Lab Seminar
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Trend
54
300mm Wafer

• throughput ??
• 2009??? 200mm wafer ??? ??
• ?? ??
• ?? ??
• ?? ?? ?? ?? ? ?? ??
• ? ??? ?? ? ??? ??

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4. ?? ? ??
MAI Lab Seminar
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Conclusion Discussion

• ??? ?? ??? ??
• ??? ?? ????
• 1.5 2 ??? ?? ??
• ?? steps? ?? ???
• ?? ??
• ??? ?? ??? ???
• ?????? ?? ?