Hari Ponnekanti has been named vice president, equipment products engineering, at Intevac Inc., effective April 1. Ponnekanti was previously director of engineering, new product development, for the Dielectric Systems and Modules Group at Applied Materials, where he led the engineering development of chemical vapor deposition products. Intevac develops imaging products for large commercial and military markets.   . . .   AIXTRON has sold an MOCVD system with a reactor capacity of 24" X 2" wafers to Uni Light Technology, an epitaxial foundry in Taoyuan, Taiwan, that produces InGaN-based LEDs.