9 research outputs found
In Situ Growth of Graphene on Polyimide for High-Responsivity Flexible PbS–Graphene Photodetectors
Graphene is an ideal material for flexible optoelectronic devices due to its excellent electrical and optical properties. However, the extremely high growth temperature of graphene has greatly limited the direct fabrication of graphene-based devices on flexible substrates. Here, we have realized in situ growth of graphene on a flexible polyimide substrate. Based on the multi-temperature-zone chemical vapor deposition cooperated with bonding a Cu-foil catalyst onto the substrate, the growth temperature of graphene was controlled at only 300 °C, enabling the structural stability of polyimide during growth. Thus, large-area high-quality monolayer graphene film was successfully in situ grown on polyimide. Furthermore, a PbS–graphene flexible photodetector was fabricated using the graphene. The responsivity of the device reached 105 A/W with 792 nm laser illumination. The in-situ growth ensures good contact between graphene and substrate; therefore, the device performance can remain stable after multiple bending. Our results provide a highly reliable and mass-producible path for graphene-based flexible devices
A guidebook of spatial transcriptomic technologies, data resources and analysis approaches
Advances in transcriptomic technologies have deepened our understanding of the cellular gene expression programs of multicellular organisms and provided a theoretical basis for disease diagnosis and therapy. However, both bulk and single-cell RNA sequencing approaches lose the spatial context of cells within the tissue microenvironment, and the development of spatial transcriptomics has made overall bias-free access to both transcriptional information and spatial information possible. Here, we elaborate development of spatial transcriptomic technologies to help researchers select the best-suited technology for their goals and integrate the vast amounts of data to facilitate data accessibility and availability. Then, we marshal various computational approaches to analyze spatial transcriptomic data for various purposes and describe the spatial multimodal omics and its potential for application in tumor tissue. Finally, we provide a detailed discussion and outlook of the spatial transcriptomic technologies, data resources and analysis approaches to guide current and future research on spatial transcriptomics
Transfer-Free CVD Growth of High-Quality Wafer-Scale Graphene at 300 °C for Device Mass Fabrication
Direct chemical vapor deposition
of graphene on semiconductors
and insulators provides high feasibility for integration of graphene
devices and semiconductor electronics. However, the current methods
typically rely on high temperatures (>1000 °C), which can
damage
the substrates. Here, a growth method for high-quality large-area
graphene at 300 °C is introduced. A multizone furnace with gradient
temperature control was designed according to a computational fluid
dynamics model. The crucial roles of the chamber pressure in the film
continuity and hydrogen composition in the graphene defect density
at low temperature were revealed. As a result, a uniform graphene
film with the Raman ratio ID/IG = 0.08 was obtained. Furthermore, a technique of laminating
single-crystal Cu foil as a sacrificial layer on the substrate was
proposed to realize transfer-free growth, and a wafer-scale graphene
transistor array was demonstrated with good performance consistency,
which paves the way for mass fabrication of graphene devices