A method for removing undesirable contaminants from a chip passivation layer surface without creating SiO2 particles on the passivation layer, wherein the undesirable contaminants include graphitic layers and fluorinated layers. The detection device has at least in one previously selected acquisition configuration, a degree of pixelation in the detection plane greater than 1 and a collimator-detector distance greater than one tenth of the septal height of the collimator. The data and FEC are related to a new channel, and the data includes a portion of data within a data packet.