Gas feeding molecular phosphorous ion source for semiconductor implanters

Area of Science:

• Materials Science
• Chemical Engineering
• Semiconductor Physics

Background:

• Phosphorus is a key dopant in semiconductor manufacturing.
• Red phosphorus is a common, stable source for phosphorus vapor (P4).
• Existing methods utilize red phosphorus for polyatomic molecular ion beams.

Purpose of the Study:

• To investigate phosphine as an alternative phosphorus vapor source.
• To generate polyatomic phosphorus ion beams using phosphine.
• To analyze the impact of process parameters on ion beam characteristics.

Main Methods:

• Utilizing phosphine (PH3) as a precursor gas.
• Employing a specialized dissociator to decompose phosphine at ~700°C.
• Heating phosphine to produce molecular hydrogen and phosphorus (P4).
• Directing reaction products to a discharge chamber for ion beam generation.

Main Results:

• Demonstrated successful generation of phosphorus ion beams from phosphine.
• Presented experimental data on the influence of discharge parameters.
• Showcased the effect of dissociator heater temperature on ion beam mass-charge state.

Conclusions:

• Phosphine is a viable alternative source for generating phosphorus ion beams.
• Process parameters significantly influence the resulting ion beam composition.
• This method offers a novel approach for semiconductor doping applications.