Abstract: A method and apparatus for chemical vapor deposition and/or hydride vapor phase epitaxial deposition are provided. The apparatus generally include a lower bottom plate and an upper bottom plate defining a first plenum. The upper bottom plate and a mid-plate positioned above the upper bottom plate define a heat exchanging channel. The mid-plate and a top plate positioned above the mid-plate define a second plenum. A plurality of gas conduits extend from the second plenum through the heat exchanging channel and the first plenum. The method generally includes flowing a first gas through a first plenum into a processing region, and flowing a second gas through a second plenum into a processing region. A heat exchanging fluid is introduced to a heat exchanging channel disposed between the first plenum and the second plenum. The first gas and the second gas are then reacted to form a film on a substrate.