Nanotechnology

Nanotechnology is the manipulation and control of matter at the nanoscale, roughly 1 to 100 nanometers, to create structures, devices or materials with novel properties. At this size, high surface area to volume and quantum effects can alter behavior, enabling functions not present in bulk materials.

Two general approaches exist: top-down, starting with larger objects and patterning nanoscale features; and bottom-up, assembling nanoscale components into larger structures. Both aim for precise control of structure, composition and interfaces, which determine material properties.

Techniques include lithography (photolithography, electron-beam), chemical synthesis and self-assembly, deposition methods such as chemical vapor deposition, and advanced imaging and measurement with scanning probe microscopy.

Applications span medicine (drug delivery and diagnostics), electronics and computing (smaller devices, quantum dots), energy (batteries and solar cells), materials science (stronger composites, coatings), and environmental sensing and remediation.

History: ideas date to Richard Feynman's 1959 talk, with the term popularized in the 1980s. The invention of the scanning tunneling microscope in 1981 enabled imaging at the atomic level, and discoveries of fullerenes (1985) and carbon nanotubes (1990s) accelerated the field.

Safety and ethics: nanoscale materials can interact with biological systems in unique ways, raising concerns about toxicity, exposure, and environmental impact. Research and regulators emphasize risk assessment, lifecycle management, standardization, and responsible innovation.

Outlook: nanotechnology remains a cross-disciplinary field spanning physics, chemistry, biology and engineering. Progress is focused on scalable manufacturing, reliable device integration, and governance that addresses safety, privacy and social implications.