Porous silicon ballistic electron emission source with a structure of metal/porous silicon/Si/metal is obtained by anodization, rapid thermal oxidation, and sputtering. The microstructures of porous silicon layers are characterized by means of scanning electron microscope. The results show that disordered pores are formed at anodization current densities of 15 mA/cm2, 30 mA/cm2, and 45 mA/cm2 for 5 min, respectively. However, straight pores are formed at anodization current densities of 60 mA/cm2, and 75 mA/cm2 for 5 min, respectively. The electron emission characteristic of porous silicon ballistic electron emission sources is measured in vacuum. The results show that electrons emitted into the vacuum from the porous silicon samples with disordered pores. Under a bias condition, injected electrons from the substrate are accelerated by the strong electric field on the surfaces of the Si nanocrystallites in disordered pores, and then emitted into the vacuum through Pt film. However, no electron emission is observed in porous silicon samples with straight pores. It attributes to the lack of Si nanocrystallites in straight pores. So there is not accelerating tunnels enough for electrons. According to disordered or straight pores, we can estimate whether PS samples emit electrons or not.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1166/jnn.2012.5421 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Steel Ball Impact on SiC/AlSi12 Interpenetrated Composite by Peridynamics.
Materials (Basel)
January 2025
CT-Lab UG (Haftungsbeschränkt), Nobelstr. 15, 70569 Stuttgart, Germany.
Silicon carbide and an aluminum alloy (SiC/AlSi12) composite are obtained during the pressurized casting process of the aluminum alloy into the SiC foam. The foam acts as a high-stiffness skeleton that strengthens the aluminum alloy matrix. The goal of the paper is to describe the behavior of the material, considering its internal structure.
View Article and Find Full Text PDFVisible-Light Photo-Iniferter Polymerization of Molecularly Imprinted Polymers for Direct Integration with Nanotransducers.
Small Methods
January 2025
Laboratory of Analytical Chemistry, Department of Biological and Environmental Sciences and Technologies (Di.S.Te.B.A.), University of Salento, via Monteroni, Lecce, 73100, Italy.
Molecularly Imprinted Polymers (MIPs) have gained prominence as synthetic receptors, combining simplicity of synthesis with robust molecular recognition akin to antibodies and enzymes. One of their main application areas is chemical sensing. However, direct integration of MIPs with nanostructured transducers, crucial for enhancing sensing capabilities and broadening MIPs sensing applications, remains limited.
View Article and Find Full Text PDFExploration of Key Factors in the Preparation of Highly Hydrophobic Silica Aerogel from Rice Husk Ash Assisted by Machine Learning.
Gels
January 2025
Key Laboratory of Original Agro-Environmental Pollution Prevention and Control (Ministry of Agriculture and Rural Affairs (MARA)), Tianjin Key Laboratory of Agro-Environment and Agro-Product Safety, Agro-Environmental Protection Institute, MARA, Tianjin 300191, China.
To expand the applications of hydrophobic silica aerogels derived from rice husk ash (HSA) through simple traditional methods (without adding special materials or processes), this paper employs machine learning to establish mathematical models to identify optimal conditions for extracting water glass and investigates how preparation conditions and heat treatment temperatures affect properties such as the porosity and hydrophobicity of HSA. The results indicate that the decision tree regression model provides the most accurate predictions for the extraction rate and modulus of water glass. Notably, the water contact angle of HSA produced using nitric acid as a catalyst can reach as high as 159.
View Article and Find Full Text PDFSensitive ratiometric detection of Fumonisin B using a reusable Ag-pSi SERS platform.
Food Chem X
January 2025
Institute of Agricultural Engineering, ARO, Volcani Institute, Rishon LeZion, Israel.
Food and agricultural commodities endure consistent contamination by mycotoxins, low molecular weight fungal metabolites, which pose severe health implications to humans together with staggering economic losses. Herein, a ratiometric aptasensor was constructed using silver-coated porous silicon (Ag-pSi) used as an efficient surface-enhanced Raman scattering (SERS) substrate. The bioassay included direct detection of fumonisin B (FB), an abundant and widespread contaminant, by a specific aptamer sequence immobilized on the porous transducer.
View Article and Find Full Text PDFProgrammable Porous Silicon Microparticles for Temporally Staged Drug Delivery in Combination Cancer Immunotherapy.
ACS Appl Mater Interfaces
January 2025
Center for Genomic Integrity, Institute for Basic Science, Ulsan 44919, Republic of Korea.
Combination therapies using checkpoint inhibitors with immunostimulatory agonists have attracted great attention due to their synergistic therapeutic effects for cancer treatment. However, such combination immunotherapies require specific timing of doses to show sufficient antitumor efficacy. Sequential treatment usually requires multiple administrations of the individual drugs at specific time points, thus increasing the complexity of the drug regimen and compromising patient compliance.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!