Heterojunction devices based on two-dimensional materials have been widely studied in the fields of electronics and optoelectronics. As the complexity of the chip system increases, the ability to ...realize multi-function in a single device is increasingly in demand. Here, we propose a multifunctional device based on graphene/silicon heterojunction, which can operate in photodetection mode or tunable rectifier mode. The heterojunction barrier is tunable by the external electric field. The photodetection range covers ultraviolet to visible, and the responsivity can reach 51 A/W and 495 A/W at 266 nm and 532 nm while keeping the off-state current at a low level of 10 −8 A. With the control of the external electric field, the device can also function as a tunable rectifier to achieve three states: positive-pass, off, and negative-pass, which can be applied in signal processing and logic circuit. The multifunctional integrated device has potential in future optoelectronic logic applications while reducing the cost and the device footprint.
p-type silicon (p-Si)/macro-assembled graphene nanofilm (nMAG)/n-type silicon (n-Si) heterojunction is utilized to fabricate near-infrared photodetector. Dual built-in electric fields were ...established in the same direction at the p-Si/nMAG and nMAG/n-Si heterojunctions, providing an enhanced electron-hole separation ability. The p-Si/nMAG/n-Si device has realized responsivities of 90 mA/W and 45 mA/W under 900 nm and 1064 nm illumination at room temperature and corresponding external quantum efficiency (EQE) of 11.8% and 5.2%, respectively, which is 30% and 45% higher than that of the single-junction nMAG/n-Si device. In this work, we applied two-dimensional (2D) carbon materials combined with monocrystalline silicon to explore complementary metal-oxide-semiconductor (CMOS) process-compatible device fabrication techniques, which paves the way to develop low-cost and large-scale near-infrared carbon-based photodetectors.
Abstract 2D materials and their heterostructures exhibit considerable potential in the development of avalanche photodetectors (APDs) with high gain, response, and signal‐to‐noise ratio. These ...materials hold promise in addressing inherent technical challenges associated with APDs, such as low light absorption coefficient, elevated noise current, and substantial power consumption due to high bias resulting in only moderate current gain. In this work, a macro‐assembled graphene nanofilm (nMAG)/epitaxial silicon (epi‐Si) vertical heterostructure photodetector with a responsivity of 0.38 A W −1 and a response time of 1.4 µs is reported. The photodetectors use high‐quality nMAG as the absorption layer and a lightly‐doped epi‐Si layer as the multiplication region under the avalanche mode to provide a high responsivity (2.51 mA W −1 ) and detectivity (2.67 × 10 9 Jones) at 1550 nm, which can achieve high‐resolution imaging. In addition, the APD displays a weak noise level and an avalanche gain of M = 1123. It can work with relatively low avalanche turn‐on voltages and achieve self‐quenching by switching from illumination to dark during avalanche multiplication, with a real‐time data transfer rate of 38 Mbps in near‐infrared light communication data links. The proposed structure enables the fabrication of high‐performance APDs in the infrared range using complementary‐metal‐oxide‐semiconductor (CMOS)‐compatible processes.
N6-methyladenosine (m
A) methylation is the most universal internal modification in eukaryotic mRNA. With elaborate functions executed by m
A writers, erasers, and readers, m
A modulation is involved ...in myriad physiological and pathological processes. Extensive studies have demonstrated m
A modulation in diverse tumours, with effects on tumorigenesis, metastasis, and resistance. Recent evidence has revealed an emerging role of m
A modulation in tumour immunoregulation, and divergent m
A methylation patterns have been revealed in the tumour microenvironment. To depict the regulatory role of m
A methylation in the tumour immune microenvironment (TIME) and its effect on immune evasion, this review focuses on the TIME, which is characterized by hypoxia, metabolic reprogramming, acidity, and immunosuppression, and outlines the m
A-regulated TIME and immune evasion under divergent stimuli. Furthermore, m
A modulation patterns in anti-tumour immune cells are summarized.
Improving the innovation capability of small and medium-sized enterprises (SMEs) is the foundation of high-quality economic development in China. In recent years, government subsidies and tax ...incentives are important measures implemented by Chinese government to support the innovation and development of SMEs. This paper selects A-share SMEs and GEM companies from 2012 to 2021 as samples to empirically exame the impact of government subsidies and tax incentives on SMEs innovation, and test the optimal range of government subsidies by building a threshold effect model. The results show that both government subsidies and tax incentives can promote the innovation of SMEs. However, government subsidies are not the more the better, there is an optimal range, in which the combination of the two can play the greatest role.
The central enterprises of China had enforced Compensation Reform Plan for Central Enterprise Responsible Persons (Reform Plan in short) in January 1st, 2015. The enforcement of this plan had ...initiated a lot of changes on compensation incentive system. Using the sample of central enterprises listed on the Shanghai and Shenzhen Exchanges from 2012 to 2016, this paper examines the effect of the Reform Plan on cost stickiness. The paper finds: (1) after the Reform Plan, the cost stickiness of central enterprises drops significantly; (2) this relationship is affect by management ownership and ownership concentration of shareholders. While the management ownership is high and ownership concentration of shareholders is low, the Reform Plan restrains cost stickiness is more significantly.
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