To apply an opaque mask on top of an imager chip er to create true dark reference pixels

 

High performance image sensors are largely used in almost all imaging space instrumentation. One of the critical performance parameter is dark current for which the absolute characterization and the post-calibration has proven to be of paramount importance. For visible image sensors, the technology to apply an opaque metal mask on top of the sensing layer is already available. This creates dark pixels, which are used for the measurement of the dark current and offset. However, for infrared detectors, such technology is not available. The proposed activity is to perform the design, the manufacturing and the electro-optical characterization of a Mercury-Cadmium Telluride (MCT) infrared detector chip on which an opaque metal mask will be implemented.

 

The activity encompasses the following tasks:

-Overview of the available techniques and process/technologies for applying opaque metal masks on detectors

-Identification of design and process limitations related to the infrared detectors

-Identification of the appropriate test structure: choice of the infrared layer/sensor and choice of the opaque mask (design + materials)

-Procurement of infrared sensor and manufacturing of the opaque mask

-Full electro-optical characterization to evaluate (a) if the presence of the mask proves beneficial for the dark current measurement accuracy and (b) any potential unwanted effects on other critical parameters

-Conclusions and recommendations for industrialization of the proposed processes and technology modifications