Abstract: A sensor element that is adapted to respond to radiation, and which is adapted to the manufacture of a sensor array is manufactured into a single crystal semiconductor means such as silicon. An anisotropically etched pit is provided under the sensing surface, and the pit generally corresponds to the geometry of the sensor element. The geometry is selected to be rectangular and falls along a selected orientation of the particular crystalline structure used for manufacture of the device to thereby allow a high density of sensor elements to provide an efficient array.