E-beam lithography
Lithography
平版印刷是由波西米亞的 阿羅斯!塞尼菲爾德 (Alois Senefelder) 於1798年發明 的
版模Ď 成品Ď
在電子製造中，我們把設計圖，
轉移到材料上形成電子結構的 過程稱做微影術Ď
Novel nanolithography techniques
E-beam FIB
SPM
Direct writing Low throughput
Imprinting
設計的圖案尺度在微米與奈米等級Ď 現有的成熟技術包括Ď
Method 方法Ď Feature Size ( mm) 尺寸大小Ď UV Photolithography UV光刻Ď 1
Laser DWW 雷射直寫Ď 1-2
Electron Beam 電子束Ď 0.25-0.1 (可以更小)
Ion Beam 離子束Ď 0.05-0.1
X-Ray Lithography X光刻Ď <0.1
光刻技術的
進展Ď
mask and maskless techniques
使用光罩的微影術Ď 不使用光罩的微影術
直寫技術(direct writing) 電子束微影，離子束微影
，雷射束Ď 一般光刻方法Ď
M.A.Schimdt MIT opencourse 3.155J/6.152J
正光阻Ď 矽晶片Ď
二氧化矽Ď 正光阻Ď
曝光Ď
顯影Ď
蝕刻Ď
M.A.Schimdt MIT opencourse 3.155J/6.152J
負光阻Ď 光罩Ď
正光阻Ď
透光部分Ď
光阻 殘留 部分Ď
光阻 殘留 部分Ď
http://britneyspears.ac/physics/fabrication/photolithography.htm
光阻厚度：0.5mm~2.5mm 轉速：1200~4800rpm 時間：30~60sec
又稱軟烤Ď
陳啟東，物理雙月刊21卷4期451(1999)
石英玻璃上鍍鉻產生不透光圖案Ď
圖案產生：e-beam 或laser-beam
顯影Ď 蝕刻鉻膜Ď
移除光阻Ď 檢查/清潔/ 覆蓋保護層Ď
修補Ď
Toppan photomask Inc.
(etch) (lift-off)
蝕刻法Ď 舉離法Ď 鋁Ď
基板Ď
光阻Ď 光阻Ď
基板Ď
利用相同的光罩，製造的圖案剛好相反Ď 陳啟東，物理雙月刊21卷4期451(1999)
From NanonScience lab, AS
SEM Ď
X Y
X
Y
Types of electron emitter
Thermionic emitters: tungsten tip or LaB6 tip
cold-cathode type
using tungsten single crystal emitters the thermally-assisted Schottky type, using emitters of zirconium oxide.
field emission guns (FEG)
Types of electron emitter
陳力俊等：材料電子顯微鏡學，精儀中心出版(1994)
Electron extraction
Brightness: Tungsten filament: LaB6: field emission=1:10:1000 Bias voltage
brightness
current
陳力俊等：材料電子顯微鏡學，精儀中心出版(1994)
Beam aperture
Limiting Aperture
( micro micro ).
Len1 Beam Limiting Aperture (Current density),
Beam
Stigmator
Astigmatism(
):
,
(Stigmator) .
Stigmator : ,
.
blanking deflectors & blanking aperture
Blenking deflector
Beam , Blanking Aperture . :
1. Beam
.
2. On/Off ,
Beam
Blanking Aperture .
SE detector
CDEM
Faraday cup
MCP
EELS Diffraction TEM
electron
SE
AES BSE
SE: depth 100A, energy<50eV BSE: energy=e-beam energy
X-ray
Auger electron: 50eV~2keV
EELS: electron energy loss spectroscopy
E-beam lithography 流程Ď
清洗晶片Ď 旋鋪光阻
並烤乾Ď 電子束曝光Ď 顯影及觀察Ď
失敗Ď
成功Ď 設計圖案Ď
高壓電子源Ď
電子鏡筒Ď
樣品室
高真空環境Ď
抽氣系統Ď X signal
Y signal
Beam blanker
樣品座Ď
中興物理 Topcon SEM +NPGS系統Ď
電子束控制器Ď
利用長鍊的聚合物有機分子，例 如壓克力(PMMA)
電子束照射後，會將鍵結打斷Ď
陳啟東，物理雙月刊21卷4期451(1999)
figures from MicroChem PMMA
基板Ď
copolymer
T-gate
雙層阻劑lift-off製程Ď
PMMA 旋鋪參數Ď
軟烤時間:
10 分鐘 (PMMA)Ď
旋鋪參數:
Step1 - 500 rpm / 10秒 Step2 - 3000 rpm / 30秒Ď
Nano-pattern generation system (NPGS)Ď
Developed by J C Nabity in 1990sĎ Virtually any SEM, STEM, or FIB can be used with NPGSĎ
Patterns are created
using DesignCADĎ
NPGS HardwareĎ
Required Connections (bold arrows):
Analog XY Inputs; +/-3v to +/-10v range typical
Picoammeter; read the beam current hitting the sample is required for
lithography.
Typical Connections (thin arrows):
Image Signal; within +/-10v; used for NPGS Alignment feature.
Blanker; within +/-5v, <200 mA; Ď
NPGS softwareĎ
Alignment (AL)Ď
Pattern writing(PG)Ď
CAD fileĎ Writing parametersĎ
Run fileĎ
Writing parametersĎ
<Alignment>
1. Origin Offset(x,y):系統原點位置[0,0]
2. Magnification:對 Alignment 時放大倍率[1000]
3. Center-to-Center Distance(nm):電子束曝光時點對點之間距離[500]
4. Line Spacing(nm):電子束掃描的間距[500]
5. Configuration Parameter:[1]
6. Measured Beam Current(pA):根據電流大小而定 7. Dwell:掃描 Alignment 的劑量[20]
<Patten>
1. Origin Offset(x,y):系統原點位置[0,0]
2. Magnification:寫圖形的放大倍率[1000]
3. Center-to-Center Distance(nm):電子束曝光時點對點之間距離[5]
4. Line Spacing(nm):電子束掃描的間距[5]
5. Configuration Parameter:[1]
6. Measured Beam Current(pA):根據電流大小而定 7. Dwell:根據圖型線寬的劑量(可選用 Area 或 Line)Ď
E-beam 停留的點位置Ď E-beam 掃描方向Ď
Center-to-centerĎ
Line spacingĎ
DosageĎ
area dose (uC/cm
2) line dose (nC/cm)
point dose (fC) Ď
DevelopĎ
顯影劑：
MIBK(Methyl isobutyl ketone)/IPA(sopropyl alcohol) 超音波震洗浸泡 約30s~60s
Rinse:
IPA
PMMA移除：
Acetone
Ď
Images from Raith
Example-
• Standard E-beam lithography and
shadow evaporation of Al on Si substrate.
Suspended mask
PMMA 4%
PMMA 6%
Ge
developping
&
dry etching
I-shape island
Metal deposition
Al2O3 tunnel barrier
Metal deposition
e beam
基板旋轉28o
金屬線位移150nm
Why aluminum?
The native oxide layer of aluminum serves as a high quality tunneling barrier
Al Al
AlOx
Oxidation parameter: Oxygen pressure 10~50mtorr time : 1min~5min
Al/AlOx/Al junction specific capacitance: 45fF/mm2
Typical Al/AlOx/Al junction capacitance: 0.5~1fF
Sample gallery
E-beam+舉離法製作 的電子元件Ď
E-beam+蝕刻法製作的 奈米結構Ď
中興物理 Topcon SEM +NPGS系統Ď
photo製程:大面積電極Ď 利用Alignment key來將 不同製程的圖案對準Ď Alignment key
E-beam製程：細部電極Ď
75nm SiN
濕蝕刻 (KOH) E-beam&乾蝕刻 (CF4 plasma)
500mm Si photo製程+濕蝕刻
:懸空薄膜Ď
E-beam製程+乾蝕刻 :奈米孔洞Ď
Photo+lift-off :大面積電極Ď
ion-beam
(back-scattering)
IC
IC
(dual beams)
liquid metal ion source (LIMS)
Most widespread are instruments using gallium(Ga) ion sources easy to build a Ga liquid metal ion source (LMIS)
W wire tip Electrode
Ga
Beam collumn
Ion energy : 5-50 keV
Beam current : tens of nanoamps
Ion Damage
Ion Energy,keV Ga Damage layer thickness, A
In Damage layer thickness, A
5 78 57
10 126 88
20 199 133
30 262 171
40 307 195
50 364 240
be implanted into the top few nanometers of the surface destructive to the specimen
sputter atoms from the surface
Dual beam system
5 to 30kV (5kV steps) 4nm at 30kV
20nA 2mm
0.5 to 15kV 5nm at 1kV
SEM column main chamber Carbon, Tungsten TEOS
TEM Nikon
http://tech.digitimes.com.tw/
1. (Precisional Cutting)
2. (Enhanced Etching Iodine/Selective Etching XeF2)
25:1(typical) 40:1(Si)
FIB assisted CVD
(Selective Deposition)
(Metal and TEOS Deposition) Pt) (W)
50 100
IC
http://tech.digitimes.com.tw/
Sample gallery
國家實驗院精儀中心Ď 蝕刻法製作的光子晶體Ď
蝕刻法製作的探針Ď
沈積法製作的懸浮結構Ď
沈積法製作的探針Ď
