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Atomic Layer Deposition (ALD) and Precursor Materials Overview

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ALD Overview
Atomic layer deposition (ALD) enables precise control at the atomic level.
The principle of atomic layer deposition (ALD) is similar to that of chemical vapor deposition (CVD), except that the ALD reaction splits the CVD reaction into two half reactions, keeping the precursor materials separate during the reaction.
This is achieved by subsequent pulses of a special precursor vapor, each of which forms approximately one atomic layer per pulse (reaction cycle). The reaction cycle is then repeated until the desired film thickness is achieved, whereas chemical vapor deposition introduces multiple precursor materials simultaneously.

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• ALD Advantages
• The most significant advantages of ALD for thin film deposition compared to other methods are reflected in four aspects: film conformality, low temperature processing, chemometric control, and intrinsic film quality related to the self-limiting and self-assembling nature of the ALD mechanism. ALD is particularly suitable for coating surfaces with ultra-high aspect ratio morphologies and surfaces that require multilayer films with high-quality interface technology.
  Atomic Layer Deposition (ALD) for Highly Controllable Thin Films
  · Film thickness based on self-limiting, self-assembly behavior with nanoscale control
  · Chemometric control of multi-component films
  · Scalable films/processes over ultra-large areas
  · Excellent reproducibility
  · Wide process window (with respect to temperature or precursor dose variation)
  · Low defect density
  · Amorphous or crystalline film types depending on substrate and temperature
  · Fine control of multilayer coatings, heterostructures, nanostructures, mixed oxides, graded indexed layers and doping
  · Standard recipes for oxides, nitrides, metals and semiconductors.
  
  ALD Materials
  
• Precursor container

• ALD Elements

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• ALD Materials

• ALD Precursor Material Applications

• ALD Process Recipe Example

TiN deposition (ALD CHAMBER)

• Recipe name: CH3-TDMAT+400W/12N*/4H*-300C
  • TiN deposition rate ~ 0.7A/cyc
  • Conductivity data: (to be added)
  • Uses Plasma of N2 & H2 gases.
  • Temperatures: 300°C (std.), 200°C
• Recipe name: CH3-TDMAT+100W/N*-300C
  • Uses Plasma of N2 only
  • Temperatures: 300°C (std.), 200°C
• Recipe name: CH3-TDMAT+100W/NH3*-300C
  • Uses Plasma of NH₃ only
  • Temperatures: 300°C (std.), 200°C

ZrO₂ deposition (ALD CHAMBER)

• Recipe name: CH3-TEMAZ+H2O-300C ("Thermal")
  • ZrO₂ deposition rate ~ 0.9-1.0A/cyc
  • Not directly characterized since results are basically the same as the HfO₂ process above.
  • Temperature variations: 300°C (std.), 200°C
• Recipe name: CH3-TEMAZ+250W/O*-300C ("Plasma")
  • Uses Oxygen plasma reactant instead of H₂O
• Recipe name: CH3-TEMAZ+O3/100mT-300C ("Ozone")
  • Uses Ozone (O₃) for reactant instead of H₂O
  • Requires Ozone generator to be turned on - ask supervisor