- Nanoelectronics and the effect of quantum confinement

Reproduction of (quantum electric) nano memories and  the effect of quantum confinement using hybrid nanolithography 

Researcher  and Author: Dr.   (   Afshin Rashid)



Note: The resulting molecularly developed graphene nanomemories  exhibit excellent programmable nanoscale memory performance compared to previous graphene memory devices and a large memory window (12 V), fast switching speed (1 μs), strong electrical reliability.

Graphene molecular nano-memory  exhibits unique electronic properties, and its small dimensions, structural robustness, and high performance make it a very promising charge storage medium for nano-memory applications. We present a set of techniques using a solution of nanoparticles, which we deposit as a very thin layer on the desired substrate, and which is used as a sacrificial layer during the nano-patterning process. 



Due to the interaction between nanoparticles, they can organize themselves and form a thin layer that creates holes between them,  this technique was originally called natural lithography  .  Due to the cohesive nature of colloidal particles and their hydrophilic property, they form a colloidal crystal with ordered pores through which the materials of interest penetrate and deposit on the substrate. For example, polystyrene latex nanospheres can be used.  The materials deposited on the nanoparticles disappear after immersing the sample in a suitable solvent and sonication.  This process is similar to a lift-off process .  The advantages of this technique include large patterns, simplicity, good resolution and the ability to combine with other lithographic techniques.  On the other hand, this technique poses problems due to the limited shapes available for the patterned functional materials, the range arrangement of the nanopatterns and the presence of point defects.    Hybrid nanolithography has also been used to perform sequential resist exposure of chemical resists enhanced by optical lithography and electron beam lithography. Directional  block copolymer nanolithography combines top-down lithography and bottom-up self-assembly of two polymers to produce high-resolution nanopatterns over large areas   .  Typically, the self-assembly of block copolymers is randomly oriented and lacks long-range order  , but the previous top-down pattern provides a substrate for directional block copolymer lithography. Hybrid nanolithography irradiation of a substrate induces preferential growth of semiconductor materials in the irradiated areas, which can be used to fabricate ordered arrays of semiconductor dots. 



Conclusion:

The resulting molecularly developed graphene nanomemories  exhibit excellent programmable nanoscale memory performance compared to previous graphene memory devices, a large memory window (12 V), fast switching speed (1 μs), and strong electrical reliability.

Researcher  and Author: Dr.   (   Afshin Rashid)

Specialized PhD in Nano-Microelectronics