Pyrolysis of dimethylhydrazine for the MOVPE growth of GaN and InN monitored by in-situ quadrupole mass spectrometry

The pyrolysis of dimethylhydrazine (DMHy) which is used as an alternative for ammonia in the MOVPE growth of nitrides has been investigated in a horizontal LP-MOVPE reactor using quadrupole mass spectrometry. The thermal decomposition rate is investigated with regard to the dependence on reactor pressure, gas flow rate and sampling position over the susceptor. The temperature for 50% decomposition is 400-600 C, which increases with lowering the pressure irrespective of the carrier gases. The results imply a strong dependence of pyrolysis rate on the pressure, namely higher pressures induce more efficient decomposition of DMHy (copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)