Solid State Circuits Technologies

The evolution of solid-state circuit technology has a long history within a relatively short period of time. This technology has lead to the modern information society that connects us and tools, a large market, and many types of products and applications. The solid-state circuit technology continuously evolves via breakthroughs and improvements every year. This book is devoted to review and present novel approaches for some of the main issues involved in this exciting and vigorous technology. The book is composed of 22 chapters, written by authors coming from 30 different institutions located in 12 different countries throughout the Americas, Asia and Europe. Thus, reflecting the wide international contribution to the book. The broad range of subjects presented in the book offers a general overview of the main issues in modern solid-state circuit technology. Furthermore, the book offers an in depth analysis on specific subjects for specialists. We believe the book is of great scientific and educational value for many readers. I am profoundly indebted to the support provided by all of those involved in the work. First and foremost I would like to acknowledge and thank the authors who worked hard and generously agreed to share their results and knowledge. Second I would like to express my gratitude to the Intech team that invited me to edit the book and give me their full support and a fruitful experience while working together to combine this book

Biosensors

A biosensor is defined as a detecting device that combines a transducer with a biologically sensitive and selective component. When a specific target molecule interacts with the biological component, a signal is produced, at transducer level, proportional to the concentration of the substance. Therefore biosensors can measure compounds present in the environment, chemical processes, food and human body at low cost if compared with traditional analytical techniques. This book covers a wide range of aspects and issues related to biosensor technology, bringing together researchers from 11 different countries. The book consists of 16 chapters written by 53 authors. The first four chapters describe several aspects of nanotechnology applied to biosensors. The subsequent section, including three chapters, is devoted to biosensor applications in the fields of drug discovery, diagnostics and bacteria detection. The principles behind optical biosensors and some of their application are discussed in chapters from 8 to 11. The last five chapters treat of microelectronics, interfacing circuits, signal transmission, biotelemetry and algorithms applied to biosensing

Prospects of nanoelectronic biosensing with high-frequency impedance spectroscopy

In recent years the possibility to combine nanoelectronics and biosensing has opened a very wide and promising field of research, which holds the potential to revolutionize analytical biology and to enable pervasive diagnostics and personalized medicine. Integrated nanoelectronic biosensor platforms based on established CMOS technology can provide compensation and calibration hardware, programmable firmware, improved sensitivity due to the very small dimensions, high parallelism, remarkable cost and size reduction and, ultimately, the vast markets needed by the semiconductor industry. As is the case for all integrated nanoelectronic sensors, reliable and affordable design is possible only if accurate models are available to elucidate and quantitatively predict the signal transduction process. However, with the exception of a few efforts, calibrated analytical and numerical models to accurately describe the response are often still lacking for most biosensor concepts. Animated by the will to bridge this gap, in this work we develop compact analytical models and complex numerical simulation tools for the study of the transduction chain in impedimetric nanoelectronic biosensors. In particular, the 3D simulator ENBIOS, entirely developed and validated during this thesis, is a general-purpose tool that can be easily expanded to include new physical effects or more sophisticated descriptions of electrolytes and analytes coupled to semiconductor devices. The models point out the existence of two relevant cut-off frequencies governing the biosensor impedimetric response, they reveal the dependencies of biosensor response to the analyte and environmental conditions and they disclose the existence of well-defined signatures in the impedance signal. The analytical and numerical tools are carefully verified and then used to examine several case studies. The first one we consider is an impedimetric nanoelectrode array biosensor. In collaboration with Twente University, we study its response to conductive and dielectric micro-particles under well controlled experimental conditions. We show that the simulation results are in very good agreement with the measurements and we provide insight on optimum detection conditions. By studying the biosensor response to small particles, like proteins, viruses or DNA, we then confirm by simulation the advantages of high frequency impedance spectroscopy, in particular the ability of AC signals at frequency above electrolyte's dielectric relaxation cut-off frequency to overcome the Debye screening and to probe the electrolyte volume with sensitivity almost independent of the particle position and charge and of salt concentration. As a second notable example we consider the case of a Silicon Nanowire (SiNW) biosensor. We perform measurements and simulations on SiNWs in AC regime in collaboration with the CEA/LETI and EPFL/CLSE laboratories. We demonstrate the operation of SiNWs in AC in particular for pH sensing applications. We finally confirm potential advantage of a SiNW biosensor working at high frequency, in order to increase the response with respect to the DC operation.Negli ultimi anni la possibilit\ue0 di combinare nanoelettronica e biosensoristica ha aperto un campo di ricerca molto vasto e promettente, che ha il potenziale di rivoluzionare la biologia analitica e di consentire diagnostica pervasiva e medicina personalizzata. Le piattaforme di biosensori nanoelettronici integrati sono potenzialmente in grado di fornire compensazioni e calibrazioni hardware, firmware programmabili, una maggiore sensibilit\ue0 a causa delle ridotte dimensioni, elevato parallelismo, riduzione notevole dei costi e delle dimensioni e i vasti mercati necessari per il settore dei semiconduttori. Come nel caso di tutti i sensori nanoelettronici integrati, un progetto affidabile e conveniente \ue8 possibile solo se sono disponibili modelli accurati per comprendere e prevedere quantitativamente il processo di trasduzione del segnale. Tuttavia, con l'eccezione di alcuni pionieristici sforzi, mancano ancora spesso modelli analitici e numerici calibrati per descrivere accuratamente la risposta della maggior parte dei concept di biosensori. Animati dalla volont\ue0 di colmare questa lacuna, in questo lavoro sviluppiamo modelli analitici compatti e complessi strumenti di simulazione numerica per lo studio della catena di trasduzione in biosensori nanoelettronici impedimetrici. In particolare, il simulatore 3D ENBIOS, interamente sviluppato e convalidato durante questa tesi, \ue8 uno strumento generale che pu\uf2 essere facilmente ampliato per includere nuovi effetti fisici o descrizioni pi\uf9 sofisticate di elettroliti e analiti accoppiati ai dispositivi a semiconduttore. I modelli rilevano l'esistenza di due frequenze di taglio rilevanti che regolano la risposta impedimetrica del biosensore, rivelano le dipendenze della risposta del biosensore all'analita e alle condizioni ambientali e l'esistenza di firme ben definite nel segnale di impedenza. Gli strumenti analitici e numerici sono attentamente verificati e poi utilizzati per esaminare diversi casi di studio. Il primo che consideriamo \ue8 un biosensore impedimetrico a matrice di nanoelettrodi. In collaborazione con l'Universit\ue0 di Twente, studiamo la sua risposta a micro-particelle conduttive e dielettriche in condizioni sperimentali ben controllate. I risultati della simulazione sono in ottimo accordo con le misure e ci forniscono informazioni sulle condizioni di rilevamento ottimali. Studiando la risposta del biosensore a piccole particelle, come proteine, virus o DNA, confermiamo quindi tramite simulazioni i vantaggi della spettroscopia di impedenza ad alta frequenza, in particolare la capacit\ue0 dei segnali in AC a frequenza superiore alla frequenza di taglio di rilassamento dielettrico dell'elettrolita di superare lo screening di Debye e di sondare il volume dell'elettrolita con una sensibilit\ue0 quasi indipendente da posizione e carica della particella e dalla concentrazione salina. Come secondo esempio notevole consideriamo il caso di un biosensore a Nanofilo di Silicio (SiNW). Eseguiamo misure e simulazioni su SiNWs in regime AC in collaborazione con i laboratori CEA / LETI ed EPFL / CLSE. Dimostriamo il funzionamento dei SiNWs in AC, in particolare per applicazioni di misura del pH. Infine, confermiamo i vantaggi potenziali di un biosensore a SiNW operante in alta frequenza, al fine di aumentare l'intensit\ue0 della risposta rispetto al caso di funzionamento in DC

Microfluidics for Biosensing

There are 12 papers published with 8 research articles, 3 review articles and 1 perspective. The topics cover: Biomedical microfluidics Lab-on-a-chip Miniaturized systems for chemistry and life science (MicroTAS) Biosensor development and characteristics Imaging and other detection technologies Imaging and signal processing Point-of-care testing microdevices Food and water quality testing and control We hope this collection could promote the development of microfluidics and point-of-care testing (POCT) devices for biosensing