Akita Elpida has accumulated a variety of element/component technologies through its development efforts and experiments such as the 20-die stack package (stacking 20 dies of 30um each in thickness) and employed them for product development and mass production, fulfilling the customers' wide-ranging needs and requests.

Wafer Thinning Technology

Crucial to development of thin packages and stacked packages is wafer thinning technology. At Akita Elpida, thinner wafer than a copier paper, enabled by its wafer back-grinding technology, is employed for mass production. Furthermore, Akita has established the back-grinding technology to enable down to 25um in thickness, the 25um thick wafer curling up like a paper or cloth. As the wafer thickness reduces, difficulties and challenges in the later production processes such as dicing, die pick-up, wire bonding, and molding significantly grow.

Wire-Bonding Technology

For development and production of thin packages and stacked packages, advanced wire bonding technology is essential. Making available a broad range of wiring such as long wire, chip to chip, overhang wire, low loop wire, and short wire, we offer best-suited wiring to achieve thin and stacked packages.

Flip Connection Technology

Crucial is flip chip connection for small, thin, high density packages. Forming protruding electrodes called "bumps" using metal material (Au) for connection, the chips are electrically and directly connected onto the substrate with the circuit surface down. Also for development of TSV (Through Silicon Via), the bump connection technology is employed for connection to TSV between the chips.

Multiple / Different dies stacking technology

Position recognition / Die attachment

Mold filling technology

Filling / Low warpage / Protection from environment

Substrate Warpage Control Technology

Thin substrate / low warpage substrate