Thin Film Deposition

Types of Thin Films Used in Semiconductor Processing Thermal Oxides Dielectric Layers Epitaxial Layers Polycrystalline Silicon Metal Films

Uses for Deposited Films

Dielectric Films Used for insulation and passivation Typically deposited via atmospheric pressure CVD, low pressure CVD, and plasma-enhanced CVD Typical films include: –Silicon Dioxide –Silicon Nitride –Low dielectric constant materials –High dielectric constant materials

Epitaxy Related to silicon crystal growth Single-crystal semiconductor layer is grown on a single-crystal substrate Homeoepitaxy if grown layer and substrate layer are the same Heteroepitaxy if the grown layer and substrate layer are different Done via: –Chemical Vapor Deposition (CVD) –Molecular Beam Epitaxy (MBE)

Lattice Matching Issues in Epitaxy

Critical Layer Thickness for Defect- Free Strained Layer Epitaxy

Why use Polysilicon?

Metal Connections

Deposition Requirements

Deposition Issues

Deposition Issues Are Related to Aspect Ratio of Features

Industry Roadmap

Deposition Tools

Atomospheric Pressure Chemical Vapor Deposition (APCVD) Hardware

Improving APCVD Uniformity

Steps in a CVD Process

Silicon Doping with Arsenic and CVD Film Growth process

Silicon APCVD Growth Rates

APCVD Modeling

Alternative Hardware (Low Pressure CVD – LPCVD)

LPCVD vs. APCVD

Plasma Enhanced CVD

High Density Plasma CVD

Physical Vapor Deposition (PVD)

PVD

DC Sputter Deposition

RF Sputter Deposition

Benefit of an RF Sputter Deposition Tool

Deposition Tools and Conditions for Common Films