A model is proposed to describe emission of light charged clusters during the cascade stage in nucleon-induced spallation reactions. It consists in implementing a surface percolation procedure into the Li\\`ege intranuclear cascade (INCL4) model: when a nucleon is ready to leave the nuclear surface, it is allowed to drag along a cluster of nucleons, under some conditions of closeness in phase space. This possibility relies on the instantaneous dynamical phase space occupancy in the nuclear surface. The following clusters are considered: $d, t,$$^3He,$$^4He$. Good agreement is obtained with experimental data relative to heavy and medium-heavy targets at two different energies. It is shown that the implementation of light cluster emission in the cascade stage also improves our previous results for residue mass spectra.
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