5kW 50kVDC Final Energy Power SupplySource Isolation BushingExtraction ElectrodeSuppression ElectrodeTerminal Electrode2kW 20kVDC Injection Power Supply500W 5kVDC Extraction Power Supply500W 5kVDC Suppression Power SupplyThe Ion SourceSuppression ElectrodeGround Electrode The Analyzer Magnet500W 5kVDC Suppression Power SupplyFocusing the Ion Beam OnMouseOver=Ground ElectrodeTerminal Isolation Bushing The Ion Beam

The Ion Beam

 

 
 Introduction
The Ion Implanter
The Vacuum system 
The Ion Source 
The Ion Beam
 Glossary
The Faraday 
Matching Network
The Magnet 
Boron Trifluoride
Charge Neutralization
 References
 
 

This clickable image map represents the typical biasing of the source and electrodes in a beam line that has three modes of operation, Drift, Post Accel, and Post Decel. Drift simple means that the energy of the ion beam does not increased or decreased after the analyzer magnet. Post accel refer to an increase in energy and post decel refers to a decrease in energy.

 Examples...
Drift
Post Accel
Post Decel
 

The Ion Source

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The Extraction, Suppression, Ground Electrodes are used for extracting positively charged ions from the source that combine downstream to form a broad beam. Individual electrodes in close proximity to the extraction electrode can be biased to inhibit back streaming of neutralizing electrons close to the source or back to the extraction electrode.

 
 

X-rays

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 Power supplies

 

The Magnet

The Magnet A mass analyzing magnet positioned along the beam path between the source and the process chamber filters ions from the beam while allowing certain other ions to enter the process chamber. The magnet includes multiple magnet pole pieces constructed from a ferromagnetic material and having inwardly facing pole surfaces.. One or more current carrying coils set up dipole magnetic fields in the deflection region near the pole pieces. Additional coils help set up a quadruple field in deflection region.

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The following equation shows the relationship between the magnetic field (B), the ion accelerating voltage (V), the mass-to-charge ratio (m/q), and the radius of ion curvature (r) in the magnetic field. In atomic units, m/q becomes m/z where z is the number of charges on the ion.

Formula

More on The Analyzing Magnet
 
 
 
 
 

 Post accel/decel Electrode

The Post accel/decel Electrode system is used for post analysis acceleration of an ion beam to a selected final energy without beam blow-up. A group of electrodes establish a non-linear voltage gradient along the beam axis for accelerating and then decelerating the beam to the selected final energy level with focusing.

Focusing of the Ion Beam

Focusing of the Ion Beam is also provided by the construction and shape of the electrodes. The suppression electrode produces a inner zero electrostatic field, and an outer electrostatic on a field such that ions entering this outer field are deflected by an amount that is a function of their distance from the edge of the inner field. The result is a focused beam having a uniform intensity over a given target area and at a given distance from the lens.
 
 
 
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More Links...

 

 
 
 
 Introduction
The Ion Implanter
The Vacuum system 
The Ion Source 
The Ion Beam
 Glossary
The Faraday 
Matching Network
The Magnet 
Boron Trifluoride
Charge Neutralization
 References
 
 

 

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This page is sponsored by Case Technology Inc. since 5/1/98.

Updated 6/6/99.