Perovskite solar cells (PSCs) are one of the promising photovoltaic technologies for solar electricity generation. NiOx is an inorganic p‐type semiconductor widely used to address the stability issue of PSCs. Although high efficiency is obtained for the devices employing NiOx as the hole transport layer, the fabrication methods have yet to be demonstrated for industrially relevant manufacturing of large‐area and high‐performance devices. Here, it is shown that these requirements can be satisfied by using the magnetron sputtering, which is well established in the industry. The limitations of low fill factor and short‐circuit current commonly observed in sputtered NiOx‐derived PSCs can be overcome through magnesium doping and low oxygen partial pressure deposition. The fabricated PSCs show a high power conversion efficiency of up to 18.5%, along with negligible hysteresis, improved ambient stability, and high reproducibility. In addition, good uniformity is also demonstrated over an area of 100 cm2. The simple and well‐established approach constitutes a reliable and scale method paving the way for the commercialization of PSCs.

Nickel ͑Ni͒ induced crystallization of amorphous silicon (a-Si) has been studied by selective deposition of Ni on a-Si thin films. The a-Si under and near the Ni-covered regions was found to be crystallized after heat treatment at 500°C from 1 to 90 h. Micro-Auger electron spectroscopy revealed that a large amount of Ni stayed in the region under the original Ni coverage, but no Ni was detected either in the crystallized region next to the Ni coverage or in the amorphous region beyond the front of the laterally crystallized Si. X-ray photoelectron spectroscopy revealed a nonuniform Ni distribution through the depth of the crystallized film under the original Ni coverage. In particular, a Ni concentration peak was found to exist at the interface of the crystallized Si and the buried oxide. It was found that a layer of 5-nm-thick Ni could effectively induce lateral crystallization of over 100 m of a-Si, but the lateral crystallization rate was found to decrease upon extended heat treatment. Transmission electron microscopy analysis showed that the crystallized film under the Ni coverage was composed of randomly oriented fine grains, while that outside the Ni coverage was mainly composed of large ͑110͒-oriented grains. A unified mechanism is proposed to explain the Ni induced crystallization of a-Si and possible reasons for the reduction in the lateral crystallization rate are discussed.

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A series of cyanine fluorophores based on fused aromatics as an electron donor for DNA sensing and two-photon bioimaging were synthesized, among which the carbazole-based biscyanine exhibits high sensitivity and efficiency as a fluorescent light-up probe for dsDNA, which shows selective binding toward the AT-rich regions. The synergetic effect of the bischromophoric skeleton gives a several-fold enhancement in a two-photon absorption cross-section as well as a 25- to 100-fold enhancement in two-photon excited fluorescence upon dsDNA binding.

Compared to conventional solid phase crystallized (SPC) thin-film transistors (TFT's), metal induced laterally crystallized (MILC) TFT's exhibit significantly enhanced performance at reduced processing temperature. It is concluded that the major improvements in MILC-TFT's result from the growth of the crystal grains in a direction longitudinal to that of the current flow, whereas in SPC-TFT's, the grain boundaries are randomly oriented. It is also observed in this work that while the MILC-TFT's are less sensitive to short-channel effects (SCE's), their leakage current exhibits higher sensitivity to channel length reduction. These differences again can be traced to the different arrangements of the grain boundaries in the two types of devices.

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