Xanoptix, a start-up based in Merrimack, New Hampshire, secured $15.2 million in additional funding for its 3D semiconductor integration and high-density parallel optics. Xanoptix is working to commercialize a new approach to semiconductor manufacturing - chip level direct die-to-die interconnection of integrated circuits, allowing system designers a modular building block approach for chip level solutions. The latest round was led by the company's primary investors: William Blair Capital Partners, Euclid SR Partners, Envest Ventures and Optical Partners. http://www.xanoptics.com