Earth with the help of semiconductor sensors

Measurement of concentration profile of oxygen in the lower thermosphere of the Earth with the help of semiconductor sensors 

The method of semiconductor sensors allows one to determine the flux of atoms, to which the sensor was exposed, from electric conductivity measurements (provided coefficients of ionization and reflection of oxygen atoms from zinc oxide films are known). In other words, the sensor technique can be used in this case as an absolute method [21]. Indeed, variation of electric conductivity of a semiconductor film Acrpi due to adsorption is known to be caused by variation of carrier concentration An in the film, rather than by variation of their mobility / [21]  

If coefficients of ionization y and reflection of of atoms for zinc oxide film are known, we have 

10 2 at-cm, where the time of measurements in the range of linearity of a semiconductor sensor is small, the flux of atoms incident of the sensor surface should be automatically restricted and terminated, in order to prolong the time of measurements in the range of linearity. This situation demonstrates the necessity of using a closed construction of the analyzer. It this case, the sensor is installed in a cavity connected with the atmosphere by a channel with a valve. 

The analyzer contains three sensitive elements (thin films of zinc oxide) two elements are used in the measurements, whereas the third one is isolated hrom the atmosphere and serves to compensate for time and temperature drifts and to exclude the influence from molecular components of the environment. 

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