טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
Ph.D Thesis
Ph.D StudentTal Shay
SubjectBio-Inspired Functional Materials
DepartmentDepartment of Chemistry
Supervisors Professor Yoav Eichen
Professor Gadi Schuster


Abstract

Although the scientific world predicts, over and over again since the 70’s, that lithography based technology is approaching its miniaturization limits, the semiconductor industry manages to overcome all predicted obstacles, maintaining and even exceeding Moore’s laws.

Nevertheless, these pessimistic predictions led to the development of alternative approaches for performing electronics and logics. Most of the alternatives offer not only smaller sizes, but also present new fabrication processes, new concepts and new operation principles.

One possible alternative is the use of organic semiconductors, namely p-conjugated oligomers and polymers. The practically limitless choice of organic materials and the abilities of some organic species to create two- and three-dimensional structures through specific and well-defined intermolecular interactions are the main advantages of the organic semiconductors.

However, to-date, these advantages of the organic semiconductors were not fully exploited, mainly due to synthetic difficulties and the tendency of the organic semiconductors to undergo non-specific intermolecular interactions and aggregate. In contrast, biology harnesses all the aforementioned advantages of organic chemistry.

Therefore, the goal of this research is to exploit the advantages of organic chemistry, namely the large variety of possible functional materials and the ability of some organic species to undergo specific and well-defined intermolecular interactions, to the field of p‑conjugated materials by using some biological concepts.

In the first part we present the preparation and characterization of a new family of p-conjugated oligomers. The attachment of DNA moieties and DNA-like moieties to one of the new p-conjugated oligomer is presented. Crystals of the self-assembled p-conjugated oligomer exhibits a reproducible hysteresis when using AFM tip as one electrode to produce I-V curves. The use of this hysteresis to generate a sub-micron memory unit is demonstrated in this work.

In the second part we explored a new concept of using p-conjugated amino-acids as building blocks for a new family of p-conjugated oligomers. We have demonstrated the p-conjugation through the peptide bond and the sequence-independence nature of the synthesis. A field effect transistor and a light emitting diode having the new p-conjugated oligomers as the active layer, demonstrate some of the potential of our approach.

In the third part we present an efficient and selective PET-based detector for alkylating agents that can detect even traces of alkylating agent. It is also shown that by using DFT calculation we can predict the possibility of a certain system to serve as PET-base detector.