Question

Differentiate between bottom up and top down method in nanofabrication process.

Answer 1

Answer -

The top down method implies that the nano structures are synthsized by removing the crystal planes that are already present in the susbstrate.

In botton up method nanostructures are systhesized into substrate by stacking atoms into each other which gives rise to crystal planes which futher stack up resulting in synthesis of nano structures.

In top down method , the building blocks are removed from substate to form the nanostructure whereas in bottom up , the building blocks are added up and stacked in substrate to form the nano structure.

Bottom up method is better than the top down method as it produces the nano structures with lesser defects.