Solid-state diffusion and conventional ion implantation are notnsuitable for source and drain regions formation of polysilicon thin-filmntransistors on glass substrates. A 30 cm diameter large-area low-energynion shower implanter with RIPE ion source and double-grid extractionnsystem was developed as a possible low-cost solution. The ion beamncurrent density for hydrogen plasma was 100 ΜA/cm2 for 3nkeV implant energy, 300 W RF power, 140 gauss magnetic field andn3×10-4 mbar pressure. The uniformity of beam currentndensity over the central 20 cm diameter was ±3.5%. Phosphorusnimplantation has been performed using a 15% PH3 in H2n gas mixture. Implantation at 3 keV for 5 min. results in annintegrated dose of 2.48×1016 cm-2 with thenconcentration peak at a depth of 8.3 nm. Planar and mesa diodesnfabricated on p-type silicon substrates have yielded fine rectifierncharacteristics. The shower implanter is thus suitable for TFTs sourcenand drain region formation
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