So-called bolometer matrices may be used for visually detecting infrared radiation. Said bolometer matrices typically consist of micromechanically produced sensor elements (e.g. on the basis of IR-sensitive resistors or diodes) that may be applied, for temperature decoupling, onto support posts above an active silicon substrate. Such individual sensors may be arranged in rows and columns, for example in a 2D grid. The sensor elements arranged in rows and columns correspond to the rows and columns of a rastered image. An electrical connection of the respective sensor elements to a readout circuit on a silicon substrate may be established by means of support posts on which the sensor elements are attached so as to be freely suspended. Due to limitations in manufacturing technology, a support post can only route one signal. For reading out a sensor signal which describes radiation impinging on a sensor element, two terminals of the sensor element may be connected to the readout circuit in each case.
FIG. 8 shows an arrangement 800 of sensor elements 810 that is known from conventional technology. The known arrangement 800 provides one support post 812, 814 each for one sensor element terminal. That is, there are two support posts 812, 814 for each sensor element in each case. In particular, the arrangement 800 shown in FIG. 8 represents a bolometer matrix without any shared support post. The terminals of the sensor elements 810 may be freely connected to a readout circuit to read out the sensor signals. In the known arrangement 800 in accordance with FIG. 8, there are no restrictions regarding the type of sensor elements 810.
FIG. 9 shows a known arrangement 900 of sensor elements 910 in accordance with EP 1530238 B1. In the known arrangement 900, one dedicated terminal is provided for each sensor element, respectively, the second terminal of the sensor element sharing a support post 914 with three further terminals of sensor elements with which it shares a corner (see FIG. 9). The arrangement 900 shown in FIG. 9 thus represents a bolometer matrix with a shared support post. The terminal shared via the shared support post 914 typically is at a constant potential. In the known arrangement 900 in accordance with FIG. 9, therefore, 1.25 support posts are associated with one sensor element. This is at the expense of a minor restriction with regard to the configuration of the sensor circuit. However, there are no restrictions regarding the type of sensor element.
A general problem of the arrangements of sensor elements described above is that the number of support posts per sensor element and, thus, area utilization is not optimized, which results in reduced sensitivity of the respective sensor elements.
USPTO Backgrounds
USPTO Backgrounds