Nanosolar, Inc.

Solexant Corporation

Other

Aeris Capital Sustainable IP Ltd.

Craig Leidholm

Brian M Sager

Martin R Roscheisen

Brent Bollman

James R Sheats

Matthew R Robinson

Sam Kao

Jeroen K J Van Duren

Damoder Reddy

Charlie Hotz

Puthur D Paulson

Methods and devices are provided for high-throughput printing of semiconductor precursor layer from microflake particles. In one embodiment, the method comprises of transforming non-planar or planar precursor materials in an appropriate vehicle under the appropriate conditions to create dispersions of planar particles with stoichiometric ratios of elements equal to that of the feedstock or precursor materials, even after settling. In particular, planar particles disperse more easily, form much denser coatings (or form coatings with more interparticle contact area), and anneal into fused, dense films at a lower temperature and/or time than their counterparts made from spherical nanoparticles. These planar particles may be microflakes that have a high aspect ratio. The resulting dense film formed from microflakes are particularly useful in forming photovoltaic devices.

High-throughput printing of semiconductor precursor layer from microflake particles

Methods and devices are provided for transforming non-planar or planar precursor materials in an appropriate vehicle under the appropriate conditions to create dispersions of planar particles with stoichiometric ratios of elements equal to that of the feedstock or precursor materials, even after selective forces settling. In particular, planar particles disperse more easily, form much denser coatings (or form coatings with more interparticle contact area), and anneal into fused, dense films at a lower temperature and/or time than their counterparts made from spherical nanoparticles. These planar particles may be nanoflakes that have a high aspect ratio. The resulting dense films formed from nanoflakes are particularly useful in forming photovoltaic devices.

High-throughput printing of semiconductor precursor layer from nanoflake particles

An absorber layer of a photovoltaic device may be formed on an aluminum or metallized polymer foil substrate. A nascent absorber layer containing one or more elements of group IB and one or more elements of group IIIA is formed on the substrate. The nascent absorber layer and/or substrate is then rapidly heated from an ambient temperature to an average plateau temperature range of between about 200&#xb0; C. and about 600&#xb0; C. and maintained in the average plateau temperature range 1 to 30 minutes after which the temperature is reduced.

Formation of photovoltaic absorber layers on foil substrates

Methods and devices are provided for absorber layers formed on foil substrate. In one embodiment, a method of manufacturing photovoltaic devices may be comprised of providing a substrate comprising of at least one electrically conductive aluminum foil substrate, at least one electrically conductive diffusion barrier layer, and at least one electrically conductive electrode layer above the diffusion barrier layer. The diffusion barrier layer may prevent chemical interaction between the aluminum foil substrate and the electrode layer. An absorber layer may be formed on the substrate. In one embodiment, the absorber layer may be a non-silicon absorber layer. In another embodiment, the absorber layer may be an amorphous silicon (doped or undoped) absorber layer. Optionally, the absorber layer may be based on organic and/or inorganic materials.

Formation of solar cells with conductive barrier layers and foil substrates

Disclosed is a novel thin film photovoltaic device and a process of making. The device comprises an interface layer between the absorber layer and the electrode resulting in an improved back contact and improved device efficiency. The interface layer comprises a material comprising a M-(Group VIA)compound, where M is a transition metal the Group VIA designates Te, Se and/or S.

Back contact for thin film solar cells

Photovoltaic devices with conductive barrier layers and foil substrates

The present invention discloses thin film photovoltaic devices comprising Group II-VI semiconductor layers with a substrate configuration having an interface layer between the absorber layer and the window layer to create improved junctions. The present invention also discloses methods for making and surface treatments for thin film photovoltaic devices comprising Group II-VI semiconductor layers with a substrate configuration to create devices with improved junctions.

Junctions in substrate solar cells

The present invention discloses thin film photovoltaic devices comprising Group II-VI semiconductor layers with a substrate configuration having an interface layer between the back electrode and the absorber layer capable of creating an ohmic contact in the device. The present invention discloses thin film photovoltaic devices comprising Group II-VI semiconductor layers with a superstrate configuration having an interface layer between the back electrode and the absorber layer capable of creating an ohmic contact in the device where the interface layer comprises nanoparticles or nanoparticles that are sintered.

An absorber layer may be formed on a substrate using atomic layer deposition reactions. An absorber layer containing elements of groups IB, IIIA and VIA may be formed by placing a substrate in a treatment chamber and performing atomic layer deposition of a group IB element and/or one or more group IIIA elements from separate sources onto a substrate to form a film. A group VIA element is then incorporated into the film and annealed to form the absorber layer. The absorber layer may be greater than about 25 nm thick. The substrate may be coiled into one or more coils in such a way that adjacent turns of the coils do not touch one another. The coiled substrate may be placed in a treatment chamber where substantially an entire surface of the one or more coiled substrates may be treated by an atomic layer deposition process. One or more group IB elements and/or one or more group IIIA elements may be deposited onto the substrate in a stoichiometrically controlled ratio by atomic layer deposition using one or more self limiting reactions.

Growing community of inventors

Sunnyvale, CA, United States of America

Craig Leidholm