The measurement accuracy in non contact profilometric techniques is generally limited by mechanical vibrations and by geometrical defaults of the micro-scanning table. In order to free the measurement from these environnemental perturbations, we describe a novel type of interferometric microscopy based on the well-known Spectroscopic Analysis of White Light Interferograms (SAWLI). The originality of the presented set-up lies in the fixation of the reference plate on the inspected object. As reference plate and sample are fixed together, the mechanical vibrations do not affect the measurements. As a result the potential nanometric accuracy of interferometric microscopy is effective. This method consists in measuring the air gap thickness between the reference plate and the sample. At the output of the spectral interferometric microscope a channelled spectrum is observed. From this signal, the spectral phase is calculated using a numerical seven points phase shifting algorithm allowing the measurement of the local height of the analyzed surface. These preliminary results demonstrate the ability of this method as a point sensor. Then this technique will be implemented in a high frequency scanning STIL technology named MPLS 180.© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.