Japanese DRAM supplier Elpida Memory has announced that it is releasing DRAM which is the industry’s firstever commercial use of HKMG (high k metal gate) technology.
The plan is to develop a two gigabit DDR2 Mobile RAM (LPDDR2) at the 40nm-class DRAM node.
HKMG uses insulator film with a high dielectric constant which reduces leakage and improves transistor performance.
Some makers of logic semiconductors have started to use HKMG, but production has been problematic.
For a start there are higher heat treatment temperatures after HKMG formation and complicated DRAM structural characteristics which need some tricky and expensive fabrication.
Elpida tells us that it has managed to lower the heat treatment load and overcome some memory device structural complications to make it all worthwhile.
HKMG reduces the electrical thickness of the gate dielectric in the transistor by around 30 percent compared to silicon oxide dielectric.
This increases DRAM performance by jacking up transistor-on current by as much as 1.7 times compared with a silicon oxide film.
It also means that transistor-off current can be lowered by a hundreth of the current levels, thereby cutting the need for juice in the standby mode of DDR2 Mobile RAM. We do hope you notice the difference in your components when it happens..