CMOS Herstellungsverfahren für Siliziumnitridwellenleiter zur Miniaturisierung von optischen Kohärenztomographiegeräten

Optical coherence tomography (OCT) is an innovative, non-contact, imaging diagnostic method, which can be considered as an optical analogue to ultrasound but in a non-invasive manner with higher resolution. In contrast to other optical microscopy methods, OCT is based on a principle, which allows separating the image resolution (transverse) from the resolution in the depth (axial). OCT has become significantly important in ophthalmology, where, by an extension of the technique, it was possible for the first time to visualize the retina of a patient in a quality that was previously only achieved by excising tissue (biopsy) with successive microscopy.
Moreover, there is an immense demand of OCT system manufacturers, driven by the needs in health care, to offer a miniaturized, cost-effective and hand-held version of this principle for diagnostic applications.
To accomplish these goals, it requires a highly interdisciplinary consortium, as it has come together for COHESION. The COHESION consortium, consisting of ams AG (AMS), an internationally active manufacturing specialists of semiconductor components, who can handle all fabrication related aspects, the two research-oriented institutions AIT Austrian Institute of Technology (AIT) and Fachhochschule Vorarlberg (FHV) with ample expertise in the design of integrated optical components, as well as the Medical University of Vienna (MUW) with their worldwide leading position in the OCT equipment research & application, is exceptional compared to national and international standards.
OCT devices consist of several bulky and expensive subcomponents such as interferometer, spectrometer and detector. In COHESION fabrication process steps will be developed, which, for the first time will enable the realization of an OCT device on a single semiconductor chip. The envisaged future application in the field of ophthalmology is only realistic for this research-driven project because the concept of COHESION, with integrated waveguides, photodiodes and electronics is not just suitable for mass production it is only possible with manufacturing processes on an industrial level.
This means that with the achievement of the goal of COHESION - the establishment of a (CMOS-based) manufacturing process suitable for mass production, which results in a demonstration of the OCT functionality - no production-technical hurdles on the path to commercialization are present. After further development the envisaged chip can be integrated in a device that costs about one-tenth as compared to the current state of the art. This will lift the OCT technology to a new level with a national and international unique selling proposition.