Liquid Phase Epitaxy (LPE) formation of localized high quality and mobility Ge & SiGe by high dose ge-implantation with laser melt annealing for 10nm and 7nm node CMOS technology

We investigated using high dose (5E16/cm²) Ge beam-line ion implantation in combination with laser melt annealing as an alternative to Ge-epi by CVD to form high quality single crystal Ge-epilayer by LPE (liquid phase epitaxy) that is very uniform, thin 10-25nm and localized for high mobility Ge-channels. The implant resulted in 7nm amorphous Ge deposition by a method called dose controlled deposition (DCD). A 515nm laser was used to vary the melt depth from 9nm to 500nm based on laser anneal pulse duration and power level. Ellipsometer was used to measure the surface amorphous layer thickness while therma-wave (TW) analysis was used to monitor Ge implant damage recovery after LPE. SIMS depth profiles showed Ge surface concentration varied from 100% down to 2% based on the laser melt depth. X-TEM analysis showed the transformation of deposited amorphous Ge surface layer to single crystal Ge after laser melt and LPE. Sb implantation at two dose levels of 3E15/cm² and 3E13/cm² was used to examine laser melt annealing effects on n-type dopant activation and electron mobility in Ge. Special Hx-probe tips on the 4PP system was required to measure sheet resistance and CAOT/DHE method was used for Differential Hall Effect measurements.