Page 67 - Vol.08

表一、氣相中奈米粒子量測儀器與方法 [5]

Instruments or Operating Commercially Measuring range Resolution Limitation: cost? Areas of Quantities and
measurement principles available? 1. current limit stability? physical application particle
techniques 2. extendible size? concentration? properties
range accuracy?
Nano-DMA Mobility analysis 1998 3-50nm (1.5-100+nm) 3% Req. charged particles Nanopart. process Size distribution;
for size and min. conc. of 100/ monitor, classifier monodisperse
distribution cm 3 nanoparticles
Nano-charger Unipolar ionic Prototype Extrinsic eff. 90% at 10% Invreased classifier Particle charge
charging 50nm, 40% at 4nm, throughput
25% at 3nm
Electrospray Electrostatic Prototype 20nm-2μm About 5% Liquid conductivity, small Low residue PSL Aerosol generator
atomization capillary tubes spheres, salt or sugar
solutions
3
Pulse height CPC Condensation Prototype 3-10nm (2-30nm) 10% Few hundred particle/cm , Air Pollution, nanometer Size distribution
and optical response sensitive to particles with low
sizing particular optical system concentration
Hypersonic Inertial impaction Prototype 3-50nm 20% Particle bouncing for large Airborne particle sizing
impactor particles, density req’d to
obtain diameter

Multiangle light Light scattering For liquids q :40-1000nm 10% Multiple scattering, does Process monitoring Intensity weighted
-1
scattering atλ=500nm not give size distribution for spheres or radius of gyration
agglomerates
3
Particle beam mass Charging/ Prototype 5-500nm 10-20% Press.>13 Pa, 10 part./cm In situ monitoring of Size distribution
spectroscopy electro- at 133 Pa, sensitive to CVD reactor
static deflection particle chemistry
9
Time of flight Electrical mobility 0.5-2nm,>10 part./cm 3 10% High concentration; limited Traansition from large Electrical mobility
ion mobility sampling capability molecular ions to distribution/size
spectrometer small particles distribution
Photon correlation Dynamic light 50-1000nm, 5% Flow interference Monitoring processes Diffusion particle size
spectroscopy for scattering <1s measurement time with rapid time weighted by light
aerosol variation scattering intensity

Mass spectrometry Mass to charge Widely available 1-300,000 atomic 0.1% Sampling into low pressure Nanoparticle mass Mass distribution
ratio in many different massunits routine; environment characterization,
forms 1,000,000 state-of- process monitoring
the-art
Electronic Particle motion in Prototype 100% collection Collects all Inexpensive, homogeneous Deposition of particles Particle sampling
precipitator an electric field efficiency for unipolarly charged sample for variety of for analysis or material
charge particles particles substrates production

以小角度 X 光繞射儀為例，偵測技
圖三、粒子對入射 X 光的散射 [6]
術的應用，是基於 X 光的波長接近
原子尺度，當具高穿透力與原子級
散射波 距波長的特殊 X 光入射到粒子時，
由於受測粒子的相鄰結晶面散射波
彼此相位相同，故而產生干涉，此
k'
晶格繞射所產生的散射波，由觀察
P 散射波與入射波的向量變化 Q 值，
Q = k-k'
入射波 θ 便可計算出該粒子內部周期結構的
Incident Waves exp (ikr ) 特徵長度。如果粒子無內部週期結
r
O k 構，可依 Fraunhofer 的繞射原理，
於 Q=1/L 處，觀察到散射強度的
變化。當觀察到的 Q 值越小時，等
同於被測量粒子的尺度越大。

NEW FAB TECHNOLOGY JOURNAL OCTOBER 2012 67