6F2 buried wordline DRAM cell for 40nm and beyond

We present a 46 nm 6F
²
buried word-line (bWL) DRAM technology, enabling the smallest cell size of 0.013 mum2 published to date. The TiN/ W buried word-line is built below the Si surface, forming a low resistive interconnect and the metal gate of the array transistors. We demonstrate high array device on-current, small parameter variability, high reliability and small parasitic capacitances, resulting in an excellent array performance. The array device can be scaled down to 30 nm without compromising its performance.