The analyzer magnet is used to select the desired ion species. As the ions travel through the magnetic field. the magnetic force serves to move the particles in a circular path, according to the right hand rule.

Here's how it works ...

Magnetostatic field can not change the kinetic energy (K.E.) of the particle, only change the direction of its velocity.

 K.E. = 0.5 mv2 = eV

The radius (R) of the circular path is proportional to the velocity of the particle. R
 = m V / q B .
 

The mass analyzing magnet positioned along the beam path between the source and the process chamber deflects ions through controlled arcuate paths to filter ions from the beam while allowing certain other ions to enter the ion process chamber. The magnet includes multiple magnet pole pieces constructed from a ferromagnetic material and having inwardly facing pole surfaces that bound at least a portion of a ion deflection region. 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 quadrapole field in deflection region. A controller electrically coupled to the coils controls current through to create the magnetic field in the deflection region near the pole pieces. United States Patent 5,554,857

This page is sponsored by Case Technology Inc. since 4/14/98.

Updated 6/6/99.