ALD Advantages
Atomic layer deposition has several advantages over other techniques due to the actual mechanism used to deposit films. ALD is especially advantageous when film quality or thickness is critical. ALD is also quite effective at coating ultra high aspect ratio substrates or substrates that would be difficult to coat with other thin film techniques.Perfect films :
- ALD provides digital thickness control to atomic level since the film is deposited one atomic layer at a time.
- Pinhole free films, even over very large areas.
- Excellent repeatability (wide process windows: ALD is not sensitive to temperature or precursor dose variations).
- Low defect density.
- Amorphous or crystalline depending on substrate and temperature.
- Digital control of sandwiches, heterostructures, nanolaminates, mixed oxides, graded index layers and doping.
- Insensitive to dust (grows underneath dust!).
- Oxides, nitrides, metals, semiconductors possible (Cambridge NanoTech provides standard recipes).
- 100% film density guarantees ideal material properties (n, Ebd, k, etc).
- Perfect 3D conformality, 100% step coverage: uniform coatings on flat, inside porous and around particle samples.
- Atomically flat and smooth coating, copies shape of substrate perfectly.
- Large area thickness uniformity.
- Easy batch scalability (precursor sources are small and stacking of substrates is possible).
- Gentle deposition process for sensitive substrates, no plasma needed (though it is available as an option).
- Low temperature deposition possible (RT-400 °C).
- Coats on everything, even on teflon.
- Excellent adhesion due to chemical bonds at the first layer.
- Low stress because of molecular self assembly.