*2.3.1. Factors influencing for MAPLE deposition*

The nature of the organic compounds can influence the deposition of a thin film. The laser parameters (fluence, wavelength, and pulse duration) can affect the quality of the thin film.

Although it is derived from PLD, MAPLE differs in certain points, namely the method of preparation of the target and mechanism of laser‐material interaction. Film roughness can be controlled by selecting correctly the appropriate laser fluence, solute concentration and substrate temperature.

### *2.3.1.1. Influence of the matrix*

MAPLE efficiency is determined by the correct choice of the solvent matrix, which has to absorb the laser energy during the deposition, thus protecting the complex organic compound.

The solvent has to satisfy the following conditions:


**Figure 15.** AFM micrographs of P(CPP:SA) 20:80 thin films deposited by MAPLE using ethyl acetate (a) and dimethyl chloride as matrix (b); typical FTIR spectra recorded for P(CPP:SA) 20:80 thin films obtained by MAPLE using ethyl acetate as matrix at a fluence of 0.3 J/cm2 (c). (Reproduced with permission from Ref. [84]).

We present an example of MAPLE thin film synthesis of poly(1,3‐bis‐(p‐carboxyphenoxy, propane)‐co‐(sebacic anhydride)) (20:80) (P(CPP:SA)20:80) using two different solvents as a matrix to protect this hydrophobic anhydride copolymer [84]. One solvent was dimethyl chloride and the other, ethyl acetate. The copolymer was successfully transferred in both cases, but the morphology of the films was quite different. AFM images presented in **Figure 15a** for

the case of ethyl acetate as the matrix reveal a granular morphology of thin films with indi‐ vidual grains with diameters of ∼400 nm. In the case of dimethyl chloride as the matrix, the thin film seems to be compact with some circular (∼500 nm in diameter) features splashed on the surface forming a layered plate‐like structure (**Figure 15b**). Ethyl acetate was selected as the best solvent based on AFM data and FTIR spectra comparison (**Figure 15c**) that showed a high resemblance between the target material and the thin film.
