Lamellar crystallization of silicon for 3-dimensional integration

In order to realize monolithic 3-dimensional integration of semiconductor devices, we must be able to obtain device-quality single-crystalline regions of semiconductor on an amorphous substrate. This must be done without exceeding the thermal budget of underlying device layers. We present simulation results that show a 532 nm laser pulse of 15 μs duration can melt and crystallize an amorphous silicon region on top of an insulating layer, without heating underlayers above 450 °C. This timescale may allow the partial melting of silicon, in which solid lamellae of submicron width and exhibiting preferential 〈1 0 0〉 orientation can form. We show that a single lamella, once formed, can solidify on the 10 μs timescale to form a single crystal 2 μm wide. With control over the location of these lamellae, they may be of use in forming single-seeded crystalline regions in which devices can be fabricated.