There are several key techniques used in nano fabrication, each with its unique advantages and challenges:
1. Lithography Lithography is a patterning process used to transfer a geometric pattern from a mask to a substrate. The most common type is photolithography, which uses light to transfer patterns. Other types include electron beam lithography and nanoimprint lithography, which offer higher resolution.
2. Chemical Vapor Deposition (CVD) Chemical Vapor Deposition is a process used to produce high-quality, high-performance solid materials. It involves the chemical reactions of gaseous reactants at high temperatures to form a thin film on a substrate. CVD is widely used for the production of nanotubes and nanowires.
3. Atomic Layer Deposition (ALD) Atomic Layer Deposition is a technique for depositing thin films one atomic layer at a time. It offers precise control over film thickness and composition, making it ideal for applications requiring uniform coatings on complex geometries.
4. Molecular Beam Epitaxy (MBE) Molecular Beam Epitaxy is a method for growing crystalline layers to fabricate semiconductor devices. It allows for the precise control of layer thickness and composition, enabling the production of ultra-thin layers and quantum dots.
5. Scanning Probe Microscopy (SPM) Scanning Probe Microscopy techniques, such as Atomic Force Microscopy (AFM) and Scanning Tunneling Microscopy (STM), are used for imaging and manipulating surfaces at the nanoscale. These tools provide high-resolution images and can be used to position atoms and molecules precisely.
