Method for preparing a self-supporting crystallized silicon thin film
AssigneeCommissariat A L'energie Atomique Et Aux Energies Alternatives
InventorsJean-Paul Garandet, Denis Camel, Béatrice Drevet
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Abstract
The invention relates to a method for preparing a self-supporting crystallized silicon thin film having a grain size of more than 1 mm. The invention also relates to the use of said method for preparing self-supporting silicon bands and to the bands thus obtained.
Claims19
A process for preparing a self-supporting crystallized silicon thin film, said process comprising at least the steps consisting in:
- (1) having a wafer of material formed from at least three different superposed films, namely a substrate film, a surface silicon film and a carbon-based sacrificial film intercalated between the substrate film and the surface film,
- (2) heating at least one zone of said wafer so as to melt the silicon present at the surface of said zone and to form an SiC film, adjacent to the film of molten silicon, by reacting said molten silicon with the carbon forming said sacrificial film,
- (3) solidifying by cooling said molten silicon zone in step (2), and
- (4) recovering the expected silicon thin film by spontaneous detachment of the SiC film from said substrate film.
(canceled)
A self-supporting silicon ribbon, whose crystallographic structure has a grain size of greater than 1 mm, obtained by a process comprising:
- (1) having a wafer of material formed from at least three different superposed films, namely a substrate film, a surface silicon film and a carbon-based sacrificial film intercalated between the substrate film and the surface film,
- (2) heating at least one zone of said wafer so as to melt the silicon present at the surface of said zone and to form an SiC film, adjacent to the film of molten silicon, by reacting said molten silicon with carbon forming said sacrificial film,
- (3) solidifying by cooling said molten silicon zone in step (2), and
- (4) recovering the expected silicon thin film by spontaneous detachment of the SiC film from said substrate film.
A process for preparing self-supporting silicon ribbons whose crystallographic structure has a grain size of greater than 1 mm using a process comprising:
- (1) having a wafer of material formed from at least three different superposed films, namely substrate film, a surface silicon film and a carbon-based sacrificial film intercalated between the substrate film and the surface film,
- (2) heating at least one zone of said wafer so as to melt the silicon present at the surface of said zone and to form an SiC film, adjacent to the film of molten silicon, by reacting said molten silicon with carbon forming said sacrificial film, silicon with carbon forming said sacrificial film,
- (3) solidifying by cooling said molten silicon zone in step (2), and
- (4) recovering the expected silicon thin film by spontaneous detachment of the SiC film from said substrate film.
Dependencies are inferred from the claim text.