Fabrication of Silicon Nanocones Using RF Microplasma Jet at Atmospheric Pressure 18th SYMPOSIUM ON PLASMA SCIENCE FOR MATERIALS (SPSM-18) ○ Zhongshi Yang Research Background Micro-analysis of the Cone Structures Mechanism of the SNC Growth Conclusions
背景背景 Synthesis of silicon and carbon nanostructures Research Background field emission devices, UV laser, FET, sensors RF microplasma jet at atmospheric pressure on Fe coated c-Si using a CH 4 -Ar mixture CNTs Nanocones Nanopillars CVD, laser ablation, RIE, electrodeposition
c-Si Fe CH 4 Ar Plasma Fabrication Conditions Fabrication Conditions Cathode: WC tube with d of 700 µm Substrate: Fe coated c-Si Fr(Ar):50sccm Fr(CH 4 ) :50 sccm D : 4 mm T s :400ºC RF power:40W
The inner diameter of Electrode : 700 µm : 400 ~ ~ 600 μ μ m m : 600 ~ ~ 800 μ μ m m B B C C 100nm SEM Image 1.5 μ m 1.5 μ m A : 400μm : 400μm
Si O 5μ m Surface Distribution of elements EDX Spectra SEM Image 5μ m C Fe Silicon nanocones (SNCs) Come-shaped products were mainly composed of silicon and SiO 2.
TEM 像 SNC A region 60 nm B region CNT SNWs 67nm 20nm 14nm Si 1 1 μ μ m m 1 1 μ μ m m EDX analysis Si nanocrystals are embedded in the cone region
Linear Surface Profile CH 4 introduction and Fe film are very important to the SNCs growth. (a) Ar & Ar+CH 4 plasma c-Si etched hole& no cones (a) Ar & Ar+CH 4 plasma c-Si etched hole & no cones (b) Ar plasma Fe/c-Si etched hole& no cones (b) Ar plasma Fe/c-Si etched hole & no cones (c) Ar+CH 4 plasma Fe/c-Si SNCs, SNWs, CNTs plasma substrate results plasma substrate results Fe/c-Si surface
② 照射時間依存 1min 1min 30min 60min 10min ・ Number density increased ・ Average size increased 1 μm H R
Growth Model of SNCs Ar plasma jet ~20 nm thick Fe layer 1 High gas temperature ( K) of Ar microplasma jet. 2 Formation of FeSix and FeCx nanoclusters. 3 Catalytic growth by a diffusion of Si and nanocrystalline silicon particles through the FeSix nanoclusters. 4 Silicon oxidation at the outer walls by the plasma heating. CH 4 T g : 2000 ~ 3000K c-Si CH 4 nc-Si particle Si oxidation
Si Nanocones (SNCs) were synthesized on Fe-coated c-Si using RF microplasma jet at atmospheric pressure. 18th SYMPOSIUM ON PLASMA SCIENCE FOR MATERIALS (SPSM-18)