METHOD FOR MAKING PYROELECTRIC SENSORS COMPRISING A THIN PYROELECTRIC FILM REQUIRING ELECTRIC POLARISATION

摘要

The invention concerns a method for making a plurality of pyroelectric sensors by forming a thin pyroelectric film (8) at the surface of a silicon (18) wafer wherein is provided an electric polarisation of said film between lower (10) and upper (6) electrodes defining pixels (4) forming said sensors. In order to protect the wafer in case of short circuit between the two electrodes of a pixel, resistors (36) are arranged in series with the lower or upper electrodes by interconnecting said electrodes at least with subassemblies to provide electric polarisation. Once said polarisation has been produced, the electrical connections (28) connecting the upper or lower electrodes are removed, to enable each pixel to supply an elementary electric signal when the sensor is operating. So as to minimise the risks of short circuit and to reduce the stray capacity of the electrodes, the upper and lower electrodes of the pixels are structured. In case of crossover of connection tracks projecting in the wafer general plane, said crossovers (40) are provided preferably between the electrodes (6, 10) and the respective resistors (36).