High vacuum is required to prevent reaction of evaporated material during flight to target. This process can coat both sides of as many as 200 wafers at a time. Uniformity is easily achieved. The energy associated with the plasma excitation stimulates the chemical reaction and enables it to occur at low temperature. This process can coat 1 side of 10 wafers at a time.
Uniformity can be difficult to achieve.
Nitride and oxide may be deposited this way. By using a patterned mask layer, etching allows the formation of patterned 'trenches'. It also etches SiO2 300X more slowly. It does not etch nitride. EDP etches SiO2 5000X more slowly.