Pulsed laser crystallization of silicon–germanium films

Structural properties of relaxed thin film germanium layers grown by low temperature RF-PECVD epitaxy on Si and Ge (100) substrates

“…Substrates were then immediately loaded into the reactor, with no load-lock chamber, and pumped down to 10 −7 mbar within 30 min. Reactive species are created from dissociation of a mixture of GeH 4 and H 2 (respectively 5 and 200 sccm) under a RF power density 50 mW.cm −2 at a total pressure of 2.6 mbar, resulting in a deposition rate of about 5 Å.min −1 and thicknesses up to 168 nm. Amorphous hydrogenated silicon (a-Si:H) layers are deposited on top of epitaxial layers, from a silane plasma under a total pressure of 0.13 mbar and RF power density of 6 mW.cm −2 (deposition rate 0.5 Å.s −1 ).…”

“…The main ways to meet this target are crystallization of amorphous materials by novel techniques that allow to preserve the substrate [2][3][4][5] or deposition of epitaxial layers, eventually combined with lift off processes for transfer on a flexible support. Within this context, the growth of high quality Germanium with a smooth surface epi-layer on Si is a crucial step for III-V materials a Electronic mail: romain.cariou@polytechnique.edu.…”

Oriented Lateral Growth and Defects in Polycrystalline-Silicon Thin Films on Glass Substrates

“…Rapid melt growth on sapphire substrates and ELC on glass substrates have been reported as techniques for the growth of SiGe thin films (Sameshima et al, 2005;Weizman et al, 2005;Koh et al, 2010;Tanaka et al, 2010) Strong lateral segregation reportedly caused the local Ge content to differ by as much as 40% from the average value (Weizman et al, 2005). Therefore, it is necessary to examine the segregation of Ge and the appropriate growth mode for alloys in order to form crystalline SiGe on glass substrates.…”

Laser crystallization for large-area electronics

“…Transient conductance measurements are useful to observe rapid melting and solidification phenomena [13,14]. Figure 1a shows the transient electrical conductance per unit area when a pulsed XeCl excimer laser with a pulse width of 30 ns was irradiated to 50-nm-thick Si films formed on a quartz substrate [15]. A laser energy density higher than 200 mJ/cm 2 was necessary to observe a significant increase in the electrical conductivity because of the high melting point of silicon films.…”