Efficient and uniform production of III-nitride films by multiwafer MOVPE

Abstract

We present results on the growth of Ga–In–Al–N films in multiwafer Planetary Reactors® with 7×2 in. wafer capacity. The unique design of these reactors allows us to combine high efficiency (Ga efficiency in GaN around 30%) and excellent uniformity. Thickness uniformities better than ±5% on a 2 in. wafer are routinely obtained. Compositional uniformity of GaInN is better than 2 nm. Wafer-to-wafer and run-to-run reproducibility concerning thickness and composition is within the 1% range. Besides this, the material grown also has a high purity. Hall mobilities higher than 500 cm 2 V −1 s −1 are obtained for GaN. Furthermore, the design of the reactors is dedicated to the growth of complex nitride heterostructures. Fast switching manifolds for various group III precursors and different carrier gases allow a flexible design of the growth runs including nucleation, bulk layers (doped/undoped) and quantum wells. The extremely low thermal mass of the reactor permits very rapid changes of the deposition temperature between room temperature and 1300°C (optional: 1600°C). Of course p- and n-type doping is also possible. Doping uniformities are below 1% indicating extremely uniform wafer temperatures. The results demonstrate that Planetary Reactors® are reliable and efficient tools for the mass production of blue-green optoelectronic devices.