REM image of the RISEQ sensor
The CiS Research Institute has developed a tiny microchip to determine the direction of light incidence. The small design and simple integrability as well as the MEMS manufacturing technology suitable for mass production distinguish the component. The monolithic sensor is based on four integrated photodiodes in a 3D-structured silicon substrate.
Sensors for detecting the angle of incidence of light are known, for example, from tracking systems of photovoltaic plants. They are used to increase energy efficiency. Typically, they consist of several discrete electronic and optical components whose assembly is complex. Due to the manufacturing process, these hybrid assemblies are relatively large and their performance parameters have a high scattering range.
The new RISEQ sensor technology of the CiS Research Institute enables the development and production of monolithically integrated, direction-sensitive sensors. The direction of light incidence can be determined to within a few degrees. The basic concept is based on the integration of four photodiodes in the walls of a cavity in the silicon (Fig. 1-3). Depending on the design, the size of the entire sensor module can be less than 1 mm³. The monolithic design of the sensor proves to be insensitive to vibrations. The RISEQ sensor technology allows for low design and manufacturing costs and minimal component dispersion as well as high reproducibility and consistency of the electrical parameters (Fig. 4).
With these properties, RISEQ sensors are attractive for all applications that require determination of the direction of light incidence. Examples include the control of modern lighting technology, beam guidance in laser technology, the control of smart displays, applications in building automation or air-conditioning technology and automotive safety.
The research and development work in the RISEQ project was funded by the Federal Ministry for Economic Affairs and Energy (Funding cpde: MF130154).
Presentation at:
Hannover Messe, 24-28 April 2017, Hannover, Hall 4 Stand F34
SMT Hybrid Packaging, 16-18 May 2017, Nuremberg, Hall 4, Booth 239B
SENSOR+TEST, 30 May – 1 June 2017, Nuremberg, Hall 1 Stand 1-150
Function
Schematic structure
The homogeneity of the four superimposed phase-shifted photodiode signals show the high quality of the microsystem technologies used