In one embodiment the present invention is a method of conducting multiple step multiple chamber chemical vapor deposition while avoiding reactant memory in the relevant reaction chambers. The method includes depositing a layer of semiconductor material on a substrate using vapor deposition in a first deposition chamber followed by evacuation of the growth chamber to reduce vapor deposition source gases remaining in the first deposition chamber after the deposition growth and prior to opening the chamber. The substrate is transferred to a second deposition chamber while isolating the first deposition chamber from the second deposition chamber to prevent reactants present in the first chamber from affecting deposition in the second chamber and while maintaining an ambient that minimizes or eliminates growth stop effects. After the transferring step, an additional layer of a different semiconductor material is deposited on the first deposited layer in the second chamber using vapor deposition.