Thin Film Processing

Thin film processing refers to techniques used to deposit and manipulate very thin layers of material (typically 1 nm – several micrometers) on a substrate such as silicon, glass, metal, or polymers with applications in: 

    • Semiconductors & microelectronics
    • Solar cells
    • Optical coatings
    • MEMS devices
    • Sensors
    • Advanced batteries
    • Fuel cells

Thin films are usually created by three major approaches.

1. Physical Vapor Deposition (PVD)

Material is physically vaporized in vacuum and then condenses onto the substrate. Common methods:

  • Thermal evaporation
  • Electron beam evaporation
  • Sputtering (RF / DC magnetron)
  • Pulsed laser deposition

Applications:

  • semiconductor metal layers
  • optical coatings
  • magnetic films

Key equipment:

  • vacuum chamber
  • targets or evaporation sources
  • plasma system

2. Chemical Vapor Deposition (CVD)

Material is deposited through chemical reactions of gases on the substrate.

Types:

  • LPCVD – low pressure CVD
  • PECVD – plasma enhanced CVD
  • MOCVD – metal-organic CVD
  • ALD – atomic layer deposition

Applications:

  • semiconductor dielectrics
  • graphene
  • coatings for solar cells

Advantages:

  • excellent uniformity
  • conformal coatings on complex surfaces

3. Solution Processing (Wet Methods)

Material is deposited from liquid precursors.

Common techniques:

  • Spin coating
  • Dip coating
  • Spray coating
  • Slot-die coating
  • Doctor blade coating
  • Sol-gel processing

Applications:

  • perovskite solar cells
  • OLED displays
  • nanomaterials
  • thin film batteries
  • research labs

This area is very popular in university research because equipment is affordable

Typical Thin Film Processing Workflow

A typical thin film device fabrication process looks like this:

  1. Substrate preparation
    • cleaning
    • plasma treatment
  2. Thin film deposition
    • spin coating / sputtering / CVD
  3. Annealing / curing
    • hotplate
    • furnace
    • rapid thermal processing
  4. Patterning
    • photolithography
    • laser patterning
  5. Etching
    • wet etching
    • dry plasma etching
  6. Characterization
    • Thickness measurement
    • SEM
    • AFM
    • XRD

 

Parameter Description
Thickness nm – μm
Uniformity across wafer
Adhesion film bonding to substrate
Roughness surface smoothness
Crystal structure amorphous vs crystalline
Stress tensile/compressive

 

Back to blog