1. Speaker: Shiuan-Li Lin Advisor : Sheng-Lung Huang
E-beam Lithography
Speaker: Shiuan-Li Lin
Advisor : Sheng-Lung Huang
Solid-State Laser Crystal and Device Laboratory

2. Outline E-beam lithography Operation & application Conclusion
1. E-beam components
2. Scanning methods
3. Exposure
4. Some type of photoresists
5. Advantages & disadvantages
Operation & application
Conclusion
Solid-State Laser Crystal and Device Laboratory
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3. E-beam components:
An electron gun or electron source that supplies the electrons.
An electron column that 'shapes' and focuses the electron beam.
A mechanical stage that positions the wafer under the electron beam.
A wafer handling system that automatically feeds wafers to the system and unloads them after processing.
A computer system that controls the equipment.

4. Scanning methods: Raster Scan:
The e-beam is swept across the entire surface, pixel by pixel, with the beam being turned on and off according to the desired pattern.
Vector Scan:
The e-beam “jumps” from one patterned area to the next, skipping unwanted areas. This makes the vector scan much faster.
Solid-State Laser Crystal and Device Laboratory
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5. Optical EBL Exposure: 1.Mask required 2.Parallel
3.Limited by wavelength of light, diffraction and resist properties
1.Serial, point by point
2.Not limited by wavelength of electrons
3.Limited by resist properties
EBL exposure is governed with the formula:
beam current ✕ exposure time
Total charge of incident electrons =
step size
=dose ✕ exposed area
Solid-State Laser Crystal and Device Laboratory
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6. Some type of photoresists:
PMMA (polymethyl methacrylate)
ultra-high resolution, high contrast positive resist.It has poor sensitivity and poor dry etch resistance,but it sticks well to almost any surface
ZEP520A
positive resists which show high resolution (rectangle pattern profile) and
dry etch resistance, suitable for various EB processes
ESPACER
1.spin coatable, no evaporation required & water soluble
2.Ebeam exposure must occur shortly after Espacer application
Solid-State Laser Crystal and Device Laboratory
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7. Scanning methods: Advantages: 1. Smaller line width than with UVL.
2. Flexible
3. Industrial application: mask making for UV lithography.
Disadvantages:
1. Electron Backscattering : when electrons are subjected directly to a surface, they tend to “scatter” quickly, causing unwanted reactions to take place outside of the focused electron beam
2. slow exposure times & high price
Solid-State Laser Crystal and Device Laboratory
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8. Operation & application
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9. Lithography steps: 2. e-beam patterning 3. Development
1. Resist Coating
Development
2-layer resist: ESPACER ZEP520A
Substrate(SiO2)

10. Operation & Application
ELS-7000(ELIONIX)
SEM observation unit
Electron gun emitter
ZrO／W Thermal Field Emission
Acceleration voltage
25, 50, 75, 100kV
Minimum line width
8~10 nm
Lithography method
direct writing with vector
scanning
Electron beam current
1×10－12 ～ 2×10－9A
Scanning field
2,400μm×2,400μm
1,200μm×1,200μm、600μm×600μm….etc
Picture element MAP
240,000×240,000dot
60,000×60,000dot
20,000×20,000dot
Solid-State Laser Crystal and Device Laboratory
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11. Operation & Application
烘烤機
旋轉塗佈機
於基板上塗佈ESPACER
Solid-State Laser Crystal and Device Laboratory
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12. Operation & Application
基板放置(需要準確放置於兩金板之間)
推送sample進腔體前,需等待小腔體之真空度達一定的標準後才可推送
Solid-State Laser Crystal and Device Laboratory
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13. Operation & Application
PICOAMMETER
Faraday cup
Solid-State Laser Crystal and Device Laboratory
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14. Operation & Application
可繪製:直線,方框,圓形,三角….
也可讀取autoCAD圖檔!
3.67μm
Solid-State Laser Crystal and Device Laboratory
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15. Conclution
E-beam lithography is particularly important in micro electronics, which require extremely precise placement of micro sized circuit elements
Electrons can be used to etch a “mask” whose patterns can be later transferred onto a substance using other techniques
乖乖?
Solid-State Laser Crystal and Device Laboratory
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16. Thanks for your listening!
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Solid-State Laser Crystal and Device Laboratory
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