A three-dimensional selenium solar cell with the structure of Au/Se/porous TiO2/compact TiO2/fluorine-doped tin oxide-coated glass plates was fabricated by an electrochemical deposition method of selenium, which can work for the extremely thin light absorber and the hole-conducting layer. The effect of experimental conditions, such as HCl and H2SeO3 in an electrochemical solution and TiO2 parti...

This work presents a technique for the generation of analog sinusoidal signals with high spectral quality and reduced circuitry resources. Two integrated demonstrators are presented to show the feasibility of the approach. The proposed generation technique is based on a modified analog filter that provides a sinusoidal output as the response to a DC input. It has the attributes of digital progr...

We connect transistors and proteins in two ways. The first is by showing that they have much in common as fundamental devices of electronics and life. The second is by describing how an evolvable wiring of electronic devices can parallel the wiring of proteins into genetic regulatory networks. We then transform this connection into a methodology for the study of the evolutionary properties of c...

An efficient approach to optimize the performance of integrated analog circuits is described. The main objectives are to speed up the design process and obtain better, possibly optimal, performance compared to manual simulation-based device sizing schemes. The automatic generation of the cost function requires only a circuit netlist, a performance specification, and process parameters supplied ...

A network for the detection of an approaching object with simple-shape recognition is proposed based on lower animal vision. The locust can detect an approaching object through a simple process in the descending contralateral movement detector (DCMD) in the locust brain, by which the approach velocity and direction of the object is determined. The frog can recognize simple shapes through a simp...

This paper presents a physically based model for the metal–oxide–semiconductor (MOS) transistor suitable for analysis and design of analog integrated circuits. Static and dynamic characteristics of the MOS field-effect transistor are accurately described by single-piece functions of two saturation currents in all regions of operation. Simple expressions for the transconductance-to-current ratio...

We propose and analyze the error and timing of solvers consisting of both analog and digital circuitry for sparse linear systems of equations. We obtain high speed, but low precision from the analog circuits. We combine this with low speed, but high precision from the digital circuits. The hybrid circuit should be faster than digital circuits alone. As a preconditioner to standard iterative sol...

The non-toxic and wide bandgap material TiO2 is explored as an n-type buffer layer on p-type Cu(In,Ga)Se2 (CIGS) absorber layer for thin film solar cells. The amorphous TiO2 thin film deposited by atomic layer deposition process at low temperatures shows conformal coverage on the CIGS absorber layer. Solar cells from non-vacuum deposited CIGS absorbers with TiO2 buffer layer result in a high sh...

Device modeling and simulation studies of a Cu(In1-x,Gax)Se2 (CIGS) thin film solar cell have been carried out. A variety of graded band-gap structures, including space charge region (SCR) grading, back surface region grading, and double grading of the CIGS absorber layer, are examined. The device physics and performance parameters for different band-gap profiles were analyzed. Based on the sim...

This paper presents a 3-state asynchronous CA that requires merely two transition rules to achieve computational universality. This universality is achieved by embedding Priese’s delay-insensitive circuit elements, called the E-element and the K-element, on the cell space of a so-called Brownian CA, which is an asynchronous CA containing local configurations that conduct a random walk in the ci...