The foevon sensor exploits the trait that different wavelenghts of light penetrate to differing depths in silicon. Thus by stacking the sensors they can leave out the colour filter and just capture the "rainbow" at different points, red being available the deepest in the chip.

As someone else noted, the FUJI SuperCCD SR seems capable of capturing 11EV, and I've seen HDR images created from single exposures with multiple raw conversions.