INDEX
EH General
EHA eng ineering
EHB EMC
EHC SCT
EHD High Power Transmission CAMR SEC
 
 
 
                                                                                                                     ALL ITEMS SOLD AND DISPOSED
 

Ion Implanter description
Ions of the doping material are produced when atoms of the dopant are fed into the ion source and undergo collisions with electrons.
Supply positive 0-10kv.
1. Electrons emitted from cathode of the source.
2. resulting collisions cause electrical discharge producing positively charged ions.
3. with negative voltage of 0-30v they are extracted from the source by the extraction lens forming a focussed ion beam.
4. Initially focussed ions accelerate in a column to energies up to 200KeV at terminal potential.
5. Through velocity a portion of secondary electrons can part from ions or be produced through collisions with stray gas molecules.
6. Electrons cannot return to the source. A secondary electron suppressor is used.
7. Accelerated beam of ions enters electrostatic lens to set up an electric quadrupole field focussing ions towards the beam tube axis.
8. To obtain required ion species magnetic field strength is altered to deflect ions of different masses through different angles.
9. The final beam passes through a second quadrople focus lens for final beam diameter adjustment to implant the wafer.
10. To deflect plate sets electrostatically scan the beam over the wafer.
11. First set for vertical deflection Y, second set for horizontal deflection X, deflection X-Y and hybrid.
12. Vertical scanner most neutral particles generate in scanning.
13. Horizontal scanner (neutral trap) 7 degree bend trapping unreflected neutral atoms.
14. Target chamber entered by beam through matrix (variable for different diameter wafers)
15. Faraday strips measure the oversized beam to ensure whole target area is implanted.
16. Electron suppressor reflects back scattered electrons at wafer surface back to wafer guaranteeing exact measuring of the implanted dose by measuring only the ion current.
17. Wafers located on 2 carrousels holding 20x3inch (75mm) wafers per deck.
18. 2 inch (50mm) wafers can be used.

Further details are available relating to each step and function as extensive detailed information has been prepared during the operations for use as a research tool.

(EHC-417 = items B-L)

A	B	C	D
E	F	G	H
I	J	K	L