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Abstract.We report on measurements of the surface acceleration for the application of dry laser cleaning. For that purpose, industrial silicon samples were irradiated by a frequency-doubled Q-switched Nd:YAG laser. The surface displacement was measured by a heterodyne interferometer and recorded by a digital storage oscilloscope. Several hundreds of shots were averaged to give smooth displacement curves which could be derived numerically. The experiments show that the highest accelerations, which are thought to be responsible for the cleaning, occur on the time scale of the laser pulse. Simple theoretical models are in good agreement with the experimental data. The maximal displacement depends only on the deposited energy, while the maximal acceleration shows also a strong dependence from the temporal pulse shape. This knowledge allows one to optimize the pulse shape for the cleaning process. 81.65.C; 79.60.Bm In order to remove particles with diameters below 1 µm from substrates, a cleaning force exceeding the strong van der Waals adhesion must be applied to the particle. Because the van der Waals force grows rapidly with decreasing particle diameter as compared to the forces used in conventional cleaning techniques (e.g., ultrasonic cleaning), these methods are not capable of removing particles below several hundreds of nanometers. A technique called dry laser cleaning has been proposed to remove such small particles from substrates [1-4]: A short laser pulse irradiates the substrate, which expands during the pulse and accelerates the particles. The particles are ejected because of their inertia at the high negative acceleration (the rapid stop of the thermal expansion) at the end of the laser pulse. PACS:Dry laser cleaning has been proposed for cleaning surfaces like hard disk heads and silicon wafers in microelectronics, in which such small particles can lead to defects on disk heads and yield loss in chip production [5].