Devices are provided for the controlled exposure of a sensor or sensor
component. The device may include a substrate; at least one reservoir
provided in the substrate; at least one sensor or sensor component
located in the at least one reservoir; at least one reservoir cap closing
an opening in the at least one reservoir to isolate the sensor or sensor
component from a selected environmental component outside of the at least
one reservoir; at least one intermediate barrier layer disposed in the at
least one reservoir between the reservoir cap and the sensor or sensor
component; and means for disintegrating the reservoir cap to expose the
sensor or sensor component to the selected environmental component.