Well‐Oriented Silicon Thin Films with High Carrier Mobility on Polycrystalline Substrates

Si thin films, grown using ion-beam-assisted deposition of buffer layers on polycrystalline metal-alloy tapes (see Figure), show out-of-plane and in-plane mosaic spreads of 0.8° and 1.3°, respectively, and a room-temperature Hall mobility of 89 cm2 V–1 s–1 for a doping concentration of 4.4 × 1016 cm–3. These results provide proof-of-concept for a promising materials technology that does not require lattice-matched, single-crystal substrates for deposition of well-oriented, high-carrier-mobility semiconductor thin films.