FeRAM is a promising new computer memory technology that can maintain its contents even when no power is applied. It has the promise to replace battery backed SRAM, E²PROM, and Flash memory in a number of standalone and embedded memory applications. Among these are smart cards, digital signal processors, and system-on-chip modules for next generation mobile technology.

Tegal is the market and technology leader in plasma etching of critical FeRAM capacitor stacks. The stack is typically composed of two electrode layers with a ferroelectric material in between. Common electrode metal materials are platinum and iridium; common ferroelectric metal oxide materials are lead zirconium titanate (PZT) and strontium bismuth tantalate (SBT). Digital information is stored by altering the crystalographic structure of the material by imposing an electric field between the electrodes. The film "remembers" the polarity of the last field it was exposed to.

The Tegal 6540 HRe^–™ is a dual-frequency CCP etch system uniquely suited to the challenges of patterning these extremely difficult films. The patented dual-frequency power configuration allows a wide range of bias voltage to be applied to the wafer for breaking strong metal oxide bonds. The CCP mode of excitation is immune to the effects of by-product redeposition on the inside surfaces of the plasma reactor. This is in sharp contrast to the ICP mode that can be effectively shut down by the redeposition of conductive metal films on the dielectric antenna window.

HRe^–™ is a trademark of Tegal Corporation