Abstract: A plurality of dual emitter integrated circuit transistor elements in a single substrate having emitters interconnected to form a matrix is programmed by passing current between emitters of selected elements to short one base-emitter junction or to short one emitter to base and collector. A programmed ROM has a programmed bit electrically represented by a transistor and an unprogrammed location electrically represented by back-to-back transistors. Alternative programming of a bit or address may provide a diode connection for a programmed matrix bit and furthermore may provide an extremely short or low storage time for a programmed matrix bit diode.