Using PLD, you can fabricate single phase films with multi phase target. But, the phase purity of the film depends on various parameters as pressure, temperature and thermodynamic expansions of the plume etc. It also depends on the % of impurity phase present in the target.

Dear Dinesh KUmar,

Are you making epitaxial films or crystallographically matched substrates, or depositing films on un-matched polycrystalline substrates. This matters a lot.

Remember PLD can provide single phase films on single crystal substrates only.

If you have a multiphase target itself, and if you are trying to deposit on single crystal substrate, maybe it will be difficult to form single phase films and epitaxy, unless the epitaxial growth conditions are properly optimized.

It all depends what is this so called multiphase. Is it a complex composition, and cannot be identified by X-ray diffraction. If identified by XRD, then what is the quantified amount ( IN percentage) of the other phase, or phases.

Mostly You need a single phase target.

But in case you are using unmatched substrates and a multi phase traget, you will end up with multi-phase polycrystalline deposits, which will necesscitate post depositions annealing, and even then you will achieve a polycrystalline film only.

So in order to get a good desired single phase film, you will need a single phase target, and a matched single crystal substrate, and appropriate growth conditions.

Any deviation in anyoaf the requirements (Target, substrate and improper growth conditions) lead to differences in the deposited layer. 

K. Sreenivas

PLD is considered as the best technique for the stichiometric transfer of the material from the target to substrate. Logically there will be transfer of the impurity material in thin film if the target is not in pure phase. We can avoid this problem by interplaying with partial pressure of the gas in which the deposition is taking place. The initial guess for the partial pressure we can easily get from the stichiometry of the material which we are interested in to deposit. Moreover the other parameters viz temp, laser energy, fluence, deposition time, laser target distance etc.have also to be optimized.