Currently, the performances of thin film solar cells are limited by poor light absorption and carrier collection. In this research, large, broadband, and polarization-insensitive light absorption enhancement was realized via integrating with unique metallic nanogratings. Through simulation, three possible mechanisms were identified to be responsible for such an enormous enhancement. A test for totaling the absorption over the solar spectrum shows an up to approximately 30% broadband absorption enhancement when comparing to bare thin film cells.

We report a 50% increase in the power conversion efficiency of InAs/GaAs quantum dot solar cells due to n-doping of the interdot space. The n-doped device was compared with GaAs reference cell, undoped, and p-doped devices. We found that the quantum dots with built-in charge (Q-BIC) enhance electron intersubband quantum dot transitions, suppress fast electron capture processes, and preclude deterioration of the open circuit voltage in the n-doped structures. These factors lead to enhanced harvesting and efficient conversion of IR energy in the Q-BIC solar cells.

High barrier Yb/p-InP metal-insulator-semiconductor (MIS) and metal-semiconductor (MS) junctions were fabricated by evaporation of Yb on InP:Zn substrates. The capacitance-voltage (C-V) and current-voltage (I-V) characteristics of these devices were measured over a wide range of temperatures. From the room-temperature forward I-V data, the values of 1.06 and 1.30 for the ideality factor (n) were obtained for the MIS and MS diodes, respectively. The higher value of n was attributed to an order of magnitude higher density of interface states in the MS junction than in the MIS diodes. The I-V/T data over the temperature range 190–400 K, indicated that the forward current transport in the Yb/p-InP MIS junction was controlled by the thermionic-field emission (TFE) mechanism. The analysis of the reverse saturation current I0 in terms of the TFE model provided a value of 1.07±0.03 V for the zero bias, zero temperature barrier height (φ0) which was in close agreement with the value of φ0=1.03±0.04 V, provided by the C-V data. For the MS diode, the temperature dependence of the forward I-V characteristics over the temperature range 250–350 K were well described by the thermionic emission process. However, the value of φ0=0.80±0.04 V, determined from the I-V data was much smaller than the value of φ0=0.96±0.04 V, obtained from the C-V data.

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Intel Moore observed an exponential doubling in the number of transistors in every 18 months through the size reduction of transistor components since 1965. In viewing of mobile computing with insatiate appetite, we explored the necessary enhancement by an increasingly maturing nanotechnology and facing the inevitable quantum-mechanical atomic and nuclei limits. Since we cannot break down the atomic size barrier, the fact implies a fundamental size limit at the atomic/nucleus scale. This means, no more simple 18-month doubling, but other forms of transistor doubling may happen at a different slope. We are particularly interested in the nano enhancement area. (i) 3 Dimensions: If the progress in shrinking the in-plane dimensions is to slow down, vertical integration can help increasing the areal device transistor density. As the devices continue to shrink into the 20 to 30 nm range, the consideration of thermal properties and transport in such devices becomes increasingly important. (ii) Quantum computing: The other types of transistor material are rapidly developed in laboratories worldwide, for example, Spintronics, Nanostorage, HP display Nanotechnology, which are modifying this Law. We shall consider the limitation of phonon engineering fundamental information unit "Qubyte" in quantum computing, Nano/Micro Electrical Mechanical System (NEMS), Carbon Nanotubes, singlelayer Graphenes, single-strip Nano-Ribbons, and so forth.

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