Comparison of remote and direct plasma silicon nitride

SiN (silicon nitride) deposited by a PECVD (plasma enhanced chemical vapor deposition) system is a more and more common method to combine ARC (antireflection coating) with surface and bulk passivation. At this moment two types of commercial industrial PECVD systems are most common: a direct plasma parallel plate reactor and a remote plasma system. For the latter the plasma activation is located remote from the wafers to avoid a possible surface damage. For mc Si the hydrogen passivation is of great importance whereas on CZ wafers this effect is negligible. Therefore we used both materials and performed a preliminary comparison of these systems. On 5" mc wafers mean efficiencies of 15.3% and on alkaline textured 5" pseudo square CZ wafers 16.9% were reached using a standard screen printing process. Together with the other characterisation methods (dark IV, SR-LBIC, reflectivity) the IV data reveal that remote and direct plasma SiN lead to comparable results.