Advent of quantum effects in nano-transistors (based on nano-microelectronics PHD) (nano- microelectronics PHD
Researcher and author: PhD student Afshin Rashid
Note: The emergence of quantum effects as the size of the transistor shrinks and reaches below 100 nm, the behavior of individual atoms gradually becomes significant.
Given the size of the silicon atom, which is about 1.46 angstroms (0.146 nm), and considering the interatomic bond distance, we conclude that when we are below 100 nm, with only a few tens of silicon atoms We're dealing. The decrease in the number of silicon atoms in the transistor makes the crystal defect problem a serious challenge. Because a slight crystalline defect, whether caused by silicon atoms or by impure atoms added to silicon, will cause much change in the electrical behavior of the transistor and remove the transistor from the intended use.
By shrinking all the horizontal and vertical dimensions of the transistor, the charge density increases in different regions of the nano-transistor or, in other words, the number of electrical charges per unit area of the nano-transistor increases. This has two negative consequences : First, by increasing the density of the electric charge, it is possible to discharge the electrical charge from the transistor insulation areas , which can damage the transistor and cause it to fail. This is similar to the discharge of excess electric charge between the cloud and the earth in the phenomenon of lightning or lightning, which ionizes air molecules into positive and negative ions. Second, by increasing the density of the electric charge, electrons may fall out of the radius range of an atom and enter the adjacent atomic radius under the influence of the pulling or scattering forces that have now increased. This What happens in quantum physics is called tunneling. The tunneling of electrons from one atom to the adjacent atom is a phenomenon that occurs very small in size between electrons. This phenomenon is also the basis of the work of some electronic components and some nanoscopes. But in the nano-transistor, this is not a useful phenomenon, since the tunneling of electrons from one atom to the adjacent atom may continue and cause an electric current. Although electric, it can be very small, but because it is unintended and unforeseen, it acts as a leakage path for the electric current and changes the electrical behavior of the nano-transistor.
Conclusion:
Shrinking transistors and moving below 100 nm in the nanotechnology range has many advantages , but it faces several challenges.