A method of etching an underlying inorganic substrate through a patterned photoresist, including exposing a structure comprising said inorganic substrate and patterned photoresist to a plasma etchant generated from a plasma source gas including at least one fluorine-comprising gas and sulfur dioxide. The opto-electronic arrangement is characterized in that the position-sensitive detector is illuminated by at least two light emission devices, to form two measuring cells with a common detector. User selected workflows are executed in conjunction with relevant external applications and the analysis result provided to the user through the user’s client application used to select the data. The phase comparator forwards the phase or frequency difference of the network transfer rate and the source sample rate to the destination port, which then generates a local clock equivalent to the source which then compiles audio data being played at the same rate in which it was sampled at the source. A calculation device determines the thickness of the body part based on this projected pattern and compares the attenuation values of the body part and the reference material at the determined thickness.