Transcript Atomic Layer Deposition

Atomic Layer Deposition - ALD
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Introduction
Example of Al2O3
ALD at MiNaLab
Deposition materials
Advantages and disadvantages
Summary
Atomic Layer Deposition
• Excellent thickness controll
and step coverage
• Self-limited process
• Developed in 1974
• First industrial use:
electrolumenicent panels
Some opportunities of ALD
• Nanolaminate:
ZrO2 and SiO2
• Coated deep trench
structure
ALD of Al2O3 on Si
ALD at MiNaLab
Al2O3, ZnO, TiO2
Thickness: sub nm - 400 nm
ALD – deposited materials
• Oxides (Al2O3, ZnO, TiO2, HfO2 , HfSiO,
La2O3, SiO2, Ta2O5)
• Nitrides (TiN, TaN, SiN, HfN, AlN)
• Sulfides (ZnS)
• Metals (Cu, W, Pt, Ru)
Applications
• High quality photonics
• Thin solarcells laminate =>
• Thin gate oxides with high dielectric
constant
• Diffusion barriers and passivation of
active layers
• Single metal coating for catalysts
Advantages of ALD
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Low temperature deposition is possible
Excellent step coverage and reproducibility
High density film and no pinholes
Easy to scale up
Disadvantages of ALD
• Expensive equipment
• Critical adjustment of the flow:
too much flow => clogging of valves
too low flow => under-performance
Summary
ALD is excellent for:
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Thin films
High density
Excellent stociometry controll
3D structures
Large area substrates: no problem 