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The Cu undercut is a recently discovered new defect generated in the wet stripping process of MoNb/Cu gate stacked electrodes for thin-film transistors (TFTs). The formation mechanism and preventive strategy of this defect were identified and investigated in this paper. The impact of stripper concentration and stripping times on the morphology and the corrosion potential (Ecorr) of Cu and MoNb were studied. It is observed that the undercut is Cu tip-deficient, not the theoretical MoNb indentation, and the undercut becomes severer with the increase in stripping times. The in-depth mechanism analysis revealed that the abnormal Cu undercut was not ascribed to the galvanic corrosion between MoNb and Cu but to the local crevice corrosion caused by the corrosive medium intruding along the MoNb/Cu interface. Based on this newly found knowledge, three possible prevention schemes (MoNiTi (abbreviated as Mo technology development (MTD) layer/Cu), MoNb/Cu/MTD, and MoNb/Cu/MoNb) were proposed. The experimental validation shows that the Cu undercut can only be completely eliminated in the MoNb/Cu/MTD triple-stacked structure with the top MTD layer as a sacrificial anode. This work provides an effective and economical method to avoid the Cu undercut defect. The obtained results can help ensure TFT yield and improve the performance of TFT devices. [ABSTRACT FROM AUTHOR]

Information about wildlife diets is crucial for comprehending how species adapt to varying environments in fragmented habitats and for developing effective conservation strategies. White‐headed langurs (Trachypithecus leucocephalus) are exclusively found in fragmented limestone forests in southwestern China. To investigate the effects of habitat fragmentation on langurs' diets, we collected published dietary data and relevant environmental factors spanning from 1996 to 2021 at two regions with different degrees of fragmentation (Banli > Bapen), from 10 studies (three of Banli and seven of Bapen). The results demonstrated that the diets of white‐headed langurs were significantly influenced by environmental factors, including habitat fragmentation, annual rainfall, and mean annual temperature. Food item diversity index was significantly and positively affected by the fragmentation index, the higher fragmentation the langurs suffered, the more diverse food items they consumed. Besides, fruit consumption was negatively influenced by annual rainfall and the consumption of other items was influenced by mean annual temperature. Notably, although there are no significant differences in the feeding proportions of food items or food item diversity indices were observed between the Banli and Bapen groups, the Banli groups extensively consumed ground‐supported kudzu (Pueraria montana var. lobata), a plant rarely recorded in the dietary preferences of the Bapen groups, implying that the large plants likely lacking in the fragmented limestone forests. Our findings provide evidence of the major impact of habitat fragmentation on the dietary composition of white‐headed langurs, highlighting the need of considering the possibility that the habitats of the white‐headed langurs have all undergone extreme fragmentation, inferring the conservation efforts should prioritize protecting native vegetation and reducing human disturbance. [ABSTRACT FROM AUTHOR]

A high mobility (29 cm2 /Vs) and high light stability oxide thin‐film transistor (TFT) with 8 mask back channel etched (BCE) structure has been fabricated. Remarkable enhancement in negative gate‐bias thermal stress with illumination has been achieved, resulting in a threshold voltage (Vth) shift of ‐0.01 V after 1 hour. A 16.0 inch WQHD 240Hz LCD NB has been developed using high mobility and high light stability oxide TFT in G8.5. [ABSTRACT FROM AUTHOR]

The etched MoNb/Cu stack film is widely used as gate electrodes for ADS Pro TFTs. The CD Bias and profile angle(PA) are two important performance parameters for wet etching. The product‐specific bottom MoNb thickness and the fluctuation of wet etching conditions(time, temperature, and Cu ion concentration) make it difficult to precisely control the etching quality, thus it is of great significance to identify the influence of the above two factors on CD Bias and PAs. In this paper, the wet etching time, temperature and Cu ion concentration are taken as independent variables, and 11 different etching conditions are arranged based on the uniform experiments design to etch MoNb/Cu samples with two different MoNb thicknesses. The experiments reseluts shows that for the etched two MoNb/Cu stacks (15/300 nm, 30/300 nm) samples, the CD Bias and PAs are in the range of 0.22~0.73 µm and 40~51°, respectively. Both the CD Bias and PAs increase with the bottom MoNb thickness, etching temperature, etching time or Cu concentration, and the PAs increases with CD Bias. The etchant may form a reflux path during the etching process, along which the etching rate decreases. The difference between the etching rates at the top and bottom of the electrode contributes to the increase of PAs and CD Bias with etching severity. In the MoNb/Cu sidewall, MoNb acts as an anode due to the low corrosion potential, and the galvanic effect leads to the acceleration of MoNb etching, which ultimately results in the increase of PA and CD Bias under the thick MoNb. [ABSTRACT FROM AUTHOR]

TFT Vth is affected by gate material, thickness and film structure. If the Al/Mo electrode is added to bottom Mo, or Al is changed to Cu, the work function of Gate increases, that is, the flat band voltage increases, and finally Vth increases. As the gate thickness increases, the gate insulator at the profile position becomes thinner, resulting in a decrease in Vth. MoNb/Cu electrode is covered with top MoNb, which inhibits the diffusion of Cu to gate insulator(GI) and reduces the dielectric loss of GI, so that Vth decreases. At the same time, Cu diffuse to GI layerr, resulting in the positive Vth shift under negative gate stressing. Once MoNb/Cu is covered with top MoNb, the diffusion of Cu ions is inhibited, Vth gradually shifts in the negative direction under negative gate stressing and the positive Vth shift is smaller under positive gate stressing, which indicates that TFT is more stable. [ABSTRACT FROM AUTHOR]

Knowledge graph and graph convolutional network used them simultaneously in collaborative filtering can greatly improve the recommendation quality. The original graph convolutional network uses feature transformation matrix in node update, which is redundant for the recommendation model. And the existing based on knowledge graph convolutional network recommendation method uses the node representation of the last convolutional layer as the final vector representation of the target node, ignoring the target node representation of the previous several layers. To solve these two problems, a light and multilayer combined recommendation with knowledge graph convolutional network (LMCR) is proposed. The algorithm removes the feature transformation matrix and preserves or removes self-connection selectively according to the sparsity of the data when performing node update operation at each convolution layer. This paper combines target node representation learned at each convolutional layer when calculating the final representation of the target node. Experiments on Movielens-20M and Last. FM datasets show that LMCR is superior to other recommendation models, and verify the effectiveness of removing feature transformation matrix and multilayer combination operation in improving recommendation performance. [ABSTRACT FROM AUTHOR]

Diet and feeding behavior data are crucial to a deep understanding of the behavioral response and adaptation of primates to a high-altitude environment. From August 2019 to June 2021, we collected data on the feeding behavior of a high-altitude rhesus macaque Macaca mulatta group from Yajiang County, Western Sichuan Plateau, which has an altitude of over 3,500 m. The results showed that feeding (33.0 ± 1.8%) and moving (28.3 ± 2.6%) were the dominant behavior of rhesus macaques. Macaques ate 193 food items, comprising 11 food categories from 90 species. Our study found that plant roots (30.9 ± 30.1%) and young leaves (28.0 ± 33.1%) were the main foods eaten by macaques. The preferred foods of rhesus macaques were young leaves, fruits, and seeds, and the consumption of these items was positively correlated with its food availability. When the availability of preferred foods was low, macaques took plant roots, barks, and fallen leaves as fallback foods. In particular, roots were a dominant food item in winter, and this way of feeding became a key survival strategy. Our results suggest that, facing the relative scarcity and strong seasonal fluctuations of food resources in high-altitude habitat, macaques adopt active foraging strategies, relying on a variety of food species and adjusting flexibly their food choices based on food availability, which may help to maximize the energy efficiency of high-altitude macaques. [ABSTRACT FROM AUTHOR]

The decay of Ion of ADS Pro‐type TFTs experienced 1ITO decap often brings about a lot of TFT devices scrapped. It is necessary and valuable to identify the reasons and to solve the Ion drop problem induced by decap. In the present work, the difference in procedure and electronic performance between the normal and the decap TFT process was first compared, then a series of controlled and confirmation experiments to get the mechanism of Ion drop were designed and carried out. It is found that not the extra etching, but the additional ITO film deposition procedure in the decap process is the cause of Ion degradation; during ITO deposition process, the plasma cleaning would lead to the plasma damage to the silicon island, and the In and O atoms in ITO target would intrude into the silicon to form p‐type doping or SiOx oxide, giving rise to the decrease of the carrier concentration and the increase of the resistance, which eventually account for the Ion drop. Finally, the measures to suppress the Ion degradation caused by 1ITO decap were proposed and verified, it shows that the decay percentage of Ion will decline from 15% in the normal decap process to 8.9%, 12.2% and 10.6% by turning off the plasma cleaning, cutting down the deposition power, and reducing the ITO annealing temperature, respectively. And when these three above methods are combined introduction together, the Ion drop after decap can be further lower to less than 5%, which meets the requirements of mass production. This study provides a way to suppress Ion degradation and a reference to optimize TFT properties and improve product yield. [ABSTRACT FROM AUTHOR]