X-FAB enhanced process improvements significantly improve photodiode response speed

     X-FAB Silicon Foundries (" X-FAB "), globally recognized for excellence in analog/mixed-signal and optoelectronics solutions, has announced improvements to the XS018180nm sensor process, expanding its range of applications. Thanks to this technological improvement, the company is now able to offer dedicated process core modules for photodiodes. Previously, the XS018 process was mainly oriented towards the manufacture of multi-pixel CMOS image sensors, while the launch of this new module is dedicated to the manufacture of photodiodes.

     With this module, X-FAB can now offer customers a choice of six different photodiodes, covering wavelengths from ultraviolet (UV) to near-infrared (NIR); The different operating parameters of this series of photodiodes mean that they can meet a wide range of customer application requirements. In addition, X-FAB will host a free webinar on Thursday, April 15, 2021, to detail the enhanced XS018 process. The seminar will be held in two sessions, one for Asian and European audiences and the other for American audiences. 

     The new X-FAB photodiode delivers best-in-class UV sensitivity, with quantum efficiency (QE) of 40% in the UVA band, 50-60% QE in the UVB band and 60% QE in the UVC band. In addition, the performance in the NIR band has also been significantly improved. At 850nm, the QE of the photodiode is 17% higher than that of conventional devices based on the original XH018 process; At 905nm, the QE increases by 5%. With around 90% QE, its eye response scheme options are well suited for ambient light sensing applications.

     One feature of the new process is that the responsiveness of the photodiode can be specified by specifying the size of the metal aperture. The output current of the photodiode can therefore be scaled between full current and no current in order to compensate for any differences caused by filtering. This in turn simplifies the amplifying circuit of the photodiode array. Other enhancements include a 10% increase in fill factor compared to earlier XH018-based devices; In this way, devices can be created that respond to lower light levels, or the chip size can be reduced to save space.

     "Through continued investment, X-FAB has built a strong optoelectronics manufacturing capability - as evidenced by the fact that more than 20 percent of mobile phones manufactured worldwide use our ambient light sensors." Luigi Di-Capua, vice president of product Marketing at X-FAB, said, "Thanks to our advances in photodiode product technology, we are now better able to meet our customers' needs for proximity sensing, spectral analysis, and optical ranging/triangulation solutions."