A5081053279- Conducting polymers and applications
- Organic Electronics and Photovoltaics
- Advanced Memory and Neural Computing
- Thin-Film Transistor Technologies
- Semiconductor materials and devices
- Electronic and Structural Properties of Oxides
- Advanced Fluorescence Microscopy Techniques
- Photoacoustic and Ultrasonic Imaging
- Computational Drug Discovery Methods
- Various Chemistry Research Topics
- Optical Imaging and Spectroscopy Techniques
- Advanced Sensor and Energy Harvesting Materials
- Machine Learning in Materials Science
- Analytical Chemistry and Sensors
- Tactile and Sensory Interactions
- Perovskite Materials and Applications
- Force Microscopy Techniques and Applications
- Semiconductor Quantum Structures and Devices
- Diamond and Carbon-based Materials Research
- Quantum Dots Synthesis And Properties
- Multisensory perception and integration
- Mechanical and Optical Resonators
- Organic Light-Emitting Diodes Research
- Ionic liquids properties and applications
- Chalcogenide Semiconductor Thin Films
University of Cambridge
2018-2024
Northwestern University
2024
National Centre of Scientific Research "Demokritos"
2012-2015
Lawrence Berkeley National Laboratory
2015
Molecular doping-the use of redox-active small molecules as dopants for organic semiconductors-has seen a surge in research interest driven by emerging applications sensing, bioelectronics, and thermoelectrics. However, molecular doping carries with it several intrinsic problems stemming directly from the character these materials. A recent breakthrough was technique based on ion-exchange, which separates redox charge compensation steps process. Here, equilibrium kinetics ion exchange model...
Doped organic semiconductors are critical to emerging device applications, including thermoelectrics, bioelectronics, and neuromorphic computing devices. It is commonly assumed that low conductivities in these materials result primarily from charge trapping by the Coulomb potentials of dopant counterions. Here, we present a combined experimental theoretical study rebutting this belief. Using newly developed doping technique based on ion exchange, prepare highly doped films with several...
Abstract The field of organic electronics has profited from the discovery new conjugated semiconducting polymers that have molecular backbones which exhibit resilience to conformational fluctuations, accompanied by charge carrier mobilities routinely cross 1 cm 2 /Vs benchmark. One such polymer is indacenodithiophene-co-benzothiadiazole. Previously understood be lacking in microstructural order, we show here direct evidence nanosized domains high order its thin films. We also demonstrate...
Abstract A key component of organic bioelectronics is electrolyte‐gated field‐effect transistors (EG‐OFETs), which have recently been used as sensors to demonstrate label‐free, single‐molecule detection. However, these devices exhibit limited stability when operated in direct contact with aqueous electrolytes. Ultrahigh demonstrated be achievable through the utilization a systematic multifactorial approach this study. EG‐OFETs operational and lifetime several orders magnitude higher than...
High levels of performance and stability have been demonstrated for conjugated polymer thin-film transistors in recent years, making them promising materials flexible electronic circuits displays. For sensing applications, however, most research efforts focusing on electrochemical devices. Here we demonstrate a highly stable biosensing platform using based the dual-gate mechanism. In this architecture signal is transduced amplified by capacitive coupling between low-k bottom dielectric...
Conjugated polymer field-effect transistors are emerging as an enabling technology for flexible electronics due to their excellent mechanical properties combined with sufficiently high charge-carrier mobilities and compatibility large-area, low-temperature processing. However, electrical stability remains a concern. ON-state (accumulation mode) bias-stress instabilities in organic semiconductors have been widely studied, multiple mitigation strategies suggested. In contrast, OFF-state...
Abstract Organic semiconductors are a family of pi‐conjugated compounds used in many applications, such as displays, bioelectronics, and thermoelectrics. However, their susceptibility to processing‐induced contamination is not well understood. Here, it shown that organic electronic devices reported so far may have been unintentionally contaminated, thus affecting performance, water uptake, thin film properties. Nuclear magnetic resonance spectroscopy detect quantify contaminants originating...
Three thiophene ring-terminated benzothieno[3,2-b]benzothiophene (BTBT) derivatives, C-C6-DBTTT, C-C12-DBTTT, and L-C12-DBTTT, were designed synthesized, differing in the isomerization of alkyl chain position as well aromatic core construction. A study crystal structure electronic properties combined with a theoretical investigation was performed to understand structure–property relationships for application these molecules organic field-effect transistors (OFETs). Different packing...
The three-dimensional imaging of mesoscopic samples with Optical Projection Tomography (OPT) has become a powerful tool for biomedical phenotyping studies. OPT uses visible light to visualize the 3D morphology large transparent samples. To enable wider application OPT, we present OptiJ, low-cost, fully open-source system capable specimens up 13 mm tall and 8 deep 50 µm resolution. OptiJ is based on off-the-shelf, easy-to-assemble optical components an ImageJ plugin library data...
Abstract Organic semiconducting polymers have attractive electronic, optical, and mechanical properties that make them materials of choice for large area flexible electronic devices. In these devices, the electronically active polymer components are micrometers in size, sport negligible performance degradation upon bending centimeter‐scale substrate onto which they integrated. A closer look at polymers, on grain‐scale smaller, is not necessary applications. emerging micromechanical...
In this work we review the development of ion beam modified silicon nitride charge trap memories. Silicon low energy (typically ~1 keV) implantation into oxide/nitride dielectric stacks may lead to two different memory structures depending on post processing steps. Annealing at 950 °C for 30 min in inert ambient implanted leads formation a nanoparticle band nitride. To be functional such structure required subsequent deposition control layer. Alternatively wet oxidation 850 15 same thick top...
In the majority of molecular optimization tasks, predictive machine learning (ML) models are limited due to unavailability and cost generating big experimental datasets on specific task. To circumvent this limitation, ML trained theoretical or indicators suitability that either publicly available inexpensive acquire. These approaches produce a set candidate molecules which have be ranked using data expert knowledge. Under assumption structure is related functionality, here we use...
Semiconductor quantum dots are considered a promising material class with the potential of highly tunable and novel optoelectronic properties. Recent research efforts have shown that dots, assembled in well-ordered 1D, 2D 3D geometries to funnel excitons via Forster Resonance Energy Transfer (FRET) through nanocrystal composite. Understanding inter dot coupling spatial extend exciton diffusion is key design for deliberate control energy transport them. In this regard, we study Förster...
Bias stress degradation in conjugated polymer field-effect transistors is a fundamental problem these disordered materials and can be traced back to interactions of the material with environmental species,1,2,3 as well fabrication-induced defects.4,5 However, effect end groups gate dielectric associated dipole-induced disorder on bias stability has not been studied so far high-performing n-type materials, such N2200.6,7 In this work, performance metrics N2200 are examined respect dielectrics...
The three-dimensional imaging of mesoscopic samples with Optical Projection Tomography (OPT) has become a powerful tool for biomedical phenotyping studies. OPT uses visible light to visualize the 3D morphology large transparent samples. To enable wider application OPT, we present OptiJ, low-cost, fully open-source system capable specimens up 13 mm tall and 8 deep 50 μm resolution. OptiJ is based on off-the-shelf, easy-to-assemble optical components an ImageJ plugin library data...
High Mobility Polymers In article number 2101019, Deepak Venkateshvaran and colleagues present how the surface nanomechanical texture of high mobility polymers used for organic electronics is quantified together with their depth-dependent viscoelastic response. Measured data properties in a well-known semiconducting polymer presented; blue represents homogeneous Young's modulus within grains, red grain boundary moduli, topography strength.