Thermal ALD

• Conformal coating can be achieved even in high aspect ratio and complex structures
• A wide variety of materials is possible with ALD, such as:
  • Oxides:
    Al₂O₃, HfO₂, SiO₂, TiO₂, SrTiO₃, Ta₂O₅, Gd₂O₃, ZrO₂, Ga₂O₃, V₂O₅, Co₃O₄, ZnO, ZnO:Al, ZnO:B, In₂O₃:H, WO₃, MoO₃, Nb₂O₅, NiO, MgO, RuO₂
  • Fluorides: MgF₂, AlF₃
  • Organic-hybrid materials: Alucone
  • Nitrides: TiN, TaN, Si₃N₄, AlN, GaN, WN, HfN, NbN, GdN, VN, ZrN
  • Metals: Pt, Ru, Pd, Ni, W
  • Sulfides: ZnS, MoS₂

Conformal coating of high aspect ratio (15:1) structure with high-rate plasma ALD SiO₂

Al₂O₃ deposited by FlexAL ALD - Courtesy by Eindhoven University of Technology

Plasma enhanced ALD (PEALD)

In addition to the benefits of thermal ALD, plasma enhanced (PEALD) allows for a wider choice of precursor chemistry with enhanced film quality:

• Plasma enables low-temperature ALD processes and the remote source maintains low plasma damage
• Eliminates the need for water as a precursor, reducing purge times between ALD cycles - especially for low temperatures
• Higher quality films through improved removal of impurities, leading to lower resistivity, higher density, etc
• Effective metal chemistry through use of hydrogen plasma
• Ability to control stoichiometry/phase
• Reduced nucleation delay
• Plasma surface treatment
• Plasma cleaning of chamber is possible for some materials

Conformal deposition of SiO₂, TiO₂ and Al₂O₃ by plasma ALD, (CC BY 4.0 license), image library at www.AtomicLimits.com, 2021

• Guaranteed processes set up by our engineers
• Plasma surface pre-treatments
• Oxides
  • Low-temperature processing with high material quality
  • Doping and mixing
• Nitrides
  • Low resistivity
  • Low oxygen content, high refractive index
• Metals
  • Low nucleation delay with plasma
  • Low-temperature deposition
• Substrate biasing:
  • During plasma, ALD to control material properties
    • Stress, density, crystallinity (and others)
  • Before plasma ALD to pre-clean substrate surfaces
    • Etches Al₂O₃, HfO₂, SiO₂, Si₃N₄
  • After plasma, ALD to modify material and surface properties
• Option to have substrate biasing for further process control and improved material properties.

2D materials

2D materials growth can also be grown by ALD which is a new development with the aim to go toward high-quality transition metal dichalcogenide (TMD) films. ALD chemistry control has the promise to be able to utilise 2D TMDs (both n-type and p-type) with their unique properties at CMOS compatible temperatures with precise digital thickness control over a large area (200 mm wafers).

Wide range of materials

A wide variety of materials is possible with ALD and a wide range of processes can be guaranteed and set up by our process engineers. For novel processes, our extensive process knowledge and vast network allow us to provide starting point recipes that should be good starting blocks to go quickly towards a robust process.

Often plasma-based processes are available utilising our plasma knowledge and handling of mass flow controller (MFC) gas mixtures including toxic gases.