Four Point Probe
and
Hall measurement
Adviser：Kuen-Hsien Wu
Student：Wei-Ming Lin
1
Outline
1. Introduction
2. Principle
3. Operation
4. Conclusions
5. References
2
Introduction
Four-point probe measurement instrument mainly used for
measuring the resistance of semiconductor thin films, that
sheet resistance.
Sheet resistance is one of the important characteristics of a
conductive material, particularly a conductive film.
Sheet resistance will be the film thickness、grain size Inch
and the impurity concentration and other factors.
Therefore, in the course of the process, often carefully
monitor sheet resistance .
3
Principle
I
ρ ＝V/I．W ．CF
Rs = V/I ．CF
V
As d/s＞20
→ CF~4.54
W
S
S
S
sample
d
4
Operation
四點探針機台
5
Operation
上機台輸入固定電流
下機台量測出電壓
6
Operation
橫桿下拉
sample
7
Operation
藍點要恆亮
Rs = 4.54 V/I
0.154767mV / 1 μ A × 4.54
=701Ω
8
Conclusions
1
Sample size and shape does not affect the measurement results,
therefore, the sample does not have to make special specifications .
2
Four-point probe measurements silicon wafer with a metal film sheet
resistance the most common method.
3
Simple and fast, but more troublesome problem is to calculation
results .
9
Introduction
In 1978, Edwin H.Hall input current in the conductor
applied magnetic field.
Conductor and the current direction the ends of the
vertical , can measure the induced voltage .
Can determine the polarity and concentration of
carriers , Known as the Hall effect .
10
Principle
Z
Bz
y
＋
VH
－
εx
εy
Vx
＋
εy ＝ VxBz
VH ＝ εyW
p-type
W
X
F＝ qVxBz
q εy ＝ qVxBz
－
正
P-type
負
n-type
ρ ＝RH / μp
11
Operation
12
Operation
將sample固定在量測基板上
13
Operation
將量測基板插入量測架上
14
Operation
在量測座上放磁石並進行量測
15
Operation
開啟量測軟體
16
Operation
出現霍爾量測系統畫面
17
Operation
輸入膜厚
18
Operation
得到data
19
Hall measurements VS. Four-point probe
Hall measurements
Special specifications specimen
★ resistivity
★ mobility
★ carrier concentration
Four-point probe
Do not have to make special
specifications
★ sheet resistance
★ sheet resistance × film thickness
＝ resistivity
20
Conclusions
1
Hall effect is mainly for detecting a semiconductor material,film
samples can be measured resistivity, carrier concentration, carrier
polarity, and mobility.
2
Rapid measurement , Simple operation, simple to operate a computer,
you can complete the measurement step , the film is detected with a
great help.
21
References
http://140.116.176.21/www/technique/SOP/SOP%204-Point%20Probe.pdf
四點探針儀器介紹
http://ezphysics.nchu.edu.tw/prophys/basicexp/expnote/hall/hall_97Feb.pdf
物理實驗-霍爾效應
http://mast-tech.com.tw/Resistivity%20Measurement.pdf
科豐國際有限公司
22
Thank
You
23