The overall objective of 3D-BRICKS is the development of a fully characterized platform for reliable, fast and inexpensive realization of 3D digital logics by self-assembled CNT-FETs. The use of 3D structures enables to achieve a very high density of semiconductor material, to date extremely challenging with conventional nanolithography, and to arrange in different aligned layers of complementary FETs to perform fundamental digital data computation. This approach relies on three important aspects: A) A set of CNTs with defined size provides large volume of semiconductor material with optimized properties; B) novel 3D DNA nanostructures where multiple nanochannels and nanoholes can be stacked in multiple layers; C) their functionalization with a library of short oligonucleotide sequences that are complementary to specific sites in computer designed DNA-nanostructures, which enables controlled semiconductor and metallic nanomaterials decoration of the biotemplate (oriented into the nanochannels and nanoholes). The decorated DNA template will provide a reliable skeleton for FETs arrangements and connection, but not less importantly, a direct strategy to implement 3D devices without the use of multiple aligned nanolithographic steps. We are introducing, for the first time in CNTs digital electronics, the use of 3D design of self-aligned CNTs as digital logics. This approach ensures a high degree of freedom in the design of the FETs and connections thanks to the high versatility of the DNA-nanotechnology. Here, the alignment of CNTs arrays at high density (close to 150 CNT/m) will be integrated with metallic/conductive pads (the different source/drain/gate connections) in a perfectly controlled 3D arrangement. Key-aspect will be the possibility to completely rinse the DNA template after the CNT connections, this in order to reduce detrimental effects on the transistor’s performance. The procedure will be complemented by using atomic layer deposition (ALD) processes to create the suitable dielectric layers within the multistack devices. The controlled size of the CNTs, with a diameter of from 0.7 to 1.4 nm and a length below 200 nm will be a fundamental aspect to facilitate their alignment and functionality. The transistors can be designed as p- and n- CNT-FETs. Additionally, a new concept where asymmetric gate designs will be adopted will enable to prepare a full family of integrated logics with a single channel (single doped CNT), which represents a new paradigm with respect to the existing nanoelectronics based on planar CNT arrays. An electronic system that is able to perform multiple digital operations with high speed and low noise will be implemented as an array of 3D CNTs complemented with conductive paths that can be also integrated thanks to DNA-nanotechnology.
Specific main objectives:
Objective 1 Development and characterization of a library of 3D DNA nanostructures with tailored geometry that can be linked at specific sites to functionalized nanomaterials.
Objective 2 Development of functionalization methods to decorate DNA with CNTs and metallic nanoparticles and nanowires at ultrahigh density.
Objective 3 Development of novel designs for 3D CNTs integrated nanoelectronics considering both p- and n- FETs or single channel designs.
Objective 4 Proof-of-concept platform of a fully characterized novel and ground-breaking nanoelectronic technology for hybrid DNA –CNTs computation based on multiple digital logics.
The highly interdisciplinary effort of 3D-BRICKS will lead to – expected results:
• development of advanced electronic technologies based on CNT decorated (hybrid) DNA-nanostructures
• highly engineered systems for molecular functionalization
• novel digital data computing concepts based on multistacked transistors
• robust platform for single or multiple digital logics implementation
• a core multifunctional platform where the above technologies are integrated
Long term vision: once reached the technological advances of 3D-BRICKS will:
• make novel technologies available for a new generation of nanoelectronics based on CNTs
• significantly advance the field of biotechnology, material science and bio-inspired electronics through new protocols and knowledge
• facilitate the development of new tools to characterize heterogeneous molecular ensembles with atomic precision
