Analog/mixed-signal foundry, X-FAB Silicon Foundries, has added five new options to its 0.6micrometer BiCMOS technology platform, two of which X-FAB boasts are 'first-of-a-kind capabilities' for the rapidly expanding optoelectronics market. One option is the Light Shield module, which overcomes previous barriers to better protect light-sensitive areas on a chip; another is the Blue pin module, which has especially high light sensitivity, said to approach the theoretical limits.
The Light Shield module protects light-sensitive areas of a chip using a special protective layer of black resistive on top of passivation. This is in contrast to the conventional way of protecting light sensitive parts, whereby an additional metal layer that reflects light is used, which creates some interference and causes parasitic capacitances. X-FAB says that its light shield layer absorbs approximately 95 percent of the visible light.
The blue PIN module uses a photodiode that has been optimised for the blue light portion of the light spectrum, and is useful for Blu-ray applications. It is sensitive to wavelengths up to 850 nanometers, making it ideal for applications from ultraviolet to infrared.
X-FAB's other new options include a Field Effect Transistor (FET) module, allowing special transistors to be used for low-noise applications; a polyimide option, to compensate for mechanical stress; and Schottky diodes with enhanced forward current capabilities. The latter is an expansion of X-FAB's portfolio of primitive devices – X-FAB claims the additional Schottky diodes are scaleable in layout and offer better current capability in forward mode.