Diffusion
물질의 확산은 1855년 Adolf Fick에 의해 유도된 Fick’s Law 를 따르며 이는 다음과 같이 표현된다.
J= -D ∂C/∂x
∂C/∂x= Concentration gradient in the x-direction [M/s]
J=Diffusion flux across unit are at right angles to the x-direction [ mol/(s∙cm^2 )]
D=Diffusion constant [ cm^2/s]
여기서 – 부호는 흐름이 높은 농
DiffusionIon Implantation
Inexpensive equipment
• One process/furnace tube
• Uniformity ± 5-10%
• Need hard mask (SiO2 or Si3N4)
• Thermodynamically controlled
• Dopants electrically active
Very expensive equipment
• Multiple processes per tool
– mass separation
• Uniformity ± 1%
• Room temperature t
Channel protein
; hydrophilic pore
Ion channel - highly selective pore
open and close
passive transport-diffuse
Nerve cell - Ion channel 이용
Ion channels ion-selective and fluctuate between open and closed states
Ion channel 의 Property
-ion selectivity
-open and close(gate)
Specific stimulus에 의해 open
Dialysis
What is dialysis?
Dialysis is a membrane process where solutes (MW~<100 Da) diffuse from one side of the membrane (feed side) to the other (dialysate or permeate side) according to their concentration gradient. First application in the 70’s.
General Principles
Separation between solutes is obtained as a result of differences in diffusion rates.
These are arising from differe
Ⅰ. 진공기술의 응용
진공기술의 응용범위는 전 산업에 걸쳐 있으며 반도체의 집적도가 높아지고 양자소자 개발 등 첨단기술이 발전하면서 그 중요성은 날로 증가하고 있다. 다음은 진공기술이 응용되고 있는 대표적 분야들이다.
- 첨단산업 : 반도체, FED
- 미래산업 : 우주항공, 핵융합, 신소재 개발