SanDisk Corp. is disclosing new details of what it believes is a big leap for data-storage chips, using an approach that may be difficult to emulate.

The Silicon Valley company, working with manufacturing partner Toshiba Corp., has been racing with other companies to store more information on chips known as flash memory. Those products, widely used in devices such as digital cameras and music players, routinely improve along with new manufacturing technology that can shrink their cells -- tiny elements on each chip that store...