Elimination of the sidewall defects in selective epitaxial growth (SEG) of silicon for a dielectric isolation technology

Selective epitaxial growth (SEG) of silicon has not had widespread use as a dielectric isolation technology due to the near sidewall defects at the SiO₂/Si interface. These defects are located in the first 1-2 μm of the SEG/sidewall SiO₂ interface. Diode junctions intersecting the sidewall and 5 μm removed from the sidewall were fabricated in SEG material using thermally grown silicon dioxide (OX) and thermally nitrided thermal silicon dioxide (NOX) as the field insulating mask. Averaged over 16 devices of each type, diodes fabricated with NOX had much better low current I-V characteristics and minimum ideality factors (1.03) than diodes fabricated with OX field oxides (1.23). Junctions intersecting the NOX field insulator had nearly identical characteristics to bulk SEG.