International Business Machines Corporation

Alta Devices, Inc.

Utica Leaseco, LLC

Daniel Guilford Patterson

David Clifford Long

Joshua Monroe Cobb

Mark J LaPlante

Uldis Artis Ziemins

James G Balz

Candace J Freedenberg

Laila S Mattos

Gang He

Michael Aaron Kadar-Kallen

Khurshed Sorabji

Andrew James Ritenour

Octavi Santiago Escala Semonin

Reto Adrian Furler

Michael Andres

A photovoltaic device and a method of making the photovoltaic device are disclosed. The photovoltaic device may include a semiconductor layer epitaxially grown using a compound semiconductor material, such as a group III-V semiconductor material, wherein a surface of the semiconductor layer is textured via one or more laser pulses of a laser. The photovoltaic device may also include a dielectric layer deposited over the textured surface of the semiconductor layer, and a back metal reflector provided on the dielectric layer. The textured surface extends a path of light traveling through the photovoltaic device to increase absorption of the light within the photovoltaic device.

Laser-textured thin-film semiconductors by melting and ablation

A method for separation of semiconductor device cell units from fabricated large-area cell units, together with a corresponding tile unit structure, are provided in which the tile unit is cut along cell unit boundaries while leaving intact a set of specified tab sections distributed along the cell unit boundaries. The tile unit may be a multi-layer composite of a semiconductor layer with a conductive metallic base supported upon a polymer layer and adhered thereto by an adhesive film, wherein tab sections are cut completely through the semiconductor layer and its metallic base from above and may also be cut partially through the polymer layer from below, leaving at least a portion of the polymer layer in place at tab sections. Tile units can be handled such that component cell units are held together by the tab sections, until a physical final separation of selected cell units.

Perforation of films for separation

A method of kerf formation and treatment for solar cells and semiconductor films and a system therefor are described. A semiconductor film is backed by a first metal layer and topped by a second metal layer. A reference feature is defined on the film. An ultraviolet laser beam is aligned to the reference feature. A kerf is cut along the reference feature, using the ultraviolet laser beam. The beam cuts through the second metal layer, through the film and through the first metal layer. Cutting leaves debris deposited on walls of the kerf. The debris is cleaned off of the walls, using an acid-based solvent. In the case of solar cells, respective first terminals of the solar cells are electrically isolated by the cleaned kerf, and respective negative terminals of the solar cells are electrically isolated by the cleaned kerf.

Laser cutting and chemical edge clean for thin-film solar cells

A method of laser cutting through dissimilar materials separated by a metal foil. A material stack includes a semiconductor layer or film, with a metal foil layer attached to the back surface. The metal foil layer is attached to an insulative support material layer. A laser parameter is selected and optimized for the material stack. A laser beam creates a kerf in the material stack down to the metal foil layer. The laser beam removes metal through the kerf primarily by gasification rather than melting. Kerf formation continues after optimization of the laser parameter for removal of material from the remaining layers. A debris field resulting from the laser cutting of the metal layer is reduced and/or a portion of the debris is removed in an assisted manner as the beam cuts. The materials are diced by cutting the kerf through all materials.

Laser cutting through two dissimilar materials separated by a metal foil

A method and system for dicing semiconductor devices from a semiconductor film. A semiconductor film, backed by a metal layer, is bonded by an adhesive layer to a flexible translucent substrate. Reference features on the film are used to describe a cutting path like a scribe line. An infrared laser beam is aligned to the scribe lines from the back surface of the flexible substrate. The infrared laser beam cuts through the flexible substrate and the majority of the thickness of the adhesive layer, cutting a first trough of a backside street along a scribe line defined by the reference features. An ultraviolet laser beam is aligned to the backside street, or to the scribe line as mapped to the back surface of the flexible substrate. The ultraviolet laser cuts through the metal layer and the semiconductor film, cutting a second trough along the scribe line. The second trough extends from the bottom of and deepens the first trough, cutting through the semiconductor film.

Two beam backside laser dicing of semiconductor films

A method and system for dicing semiconductor devices from semiconductor thin films. A semiconductor film, backed by a metal layer, is bonded by an adhesive layer to a flexible translucent substrate. Reference features define device boundaries. An ultraviolet laser beam is aligned to the reference features and cuts through the semiconductor film, the metal layer and partially into the adhesive layer, cutting a frontside street along a real or imaginary scribe line on the cutting path. An infrared laser beam is aligned to the trough of the frontside street from the back surface of the flexible substrate, or the scribe lines are mapped to the back surface of the flexible substrate. The infrared laser beam cuts through the flexible substrate and the majority of the thickness of the adhesive layer, cutting a backside street along the scribe line. The backside street overlaps or cuts through to the frontside street, thereby separating the semiconductor devices.

Aligned frontside backside laser dicing of semiconductor films

Method for creation of inclined microstructures using a scanned laser image

A desired design for electronic structures is converted into a graphic design format and sorted into a pseudo-raster format corresponding to scan lines. A laser or other machining beam is controlled by a separate tracking beam utilizing a mid-objective scanning system. The firing frequency of the machining beam is determined by the position of the tracking beam on a detector, as compared to the scan line data. Accuracy is verified by detection of plume or spectra generated during machining. Alignment of the machining and tracking beams is by interferometric methods. The system improves optical performance parameters of telecentricity, angle of scanned beam line, location of line in which the scanned line resides, astigmatism and field curvature.

Multi-wavelength programmable laser processing mechanisms and apparatus

A desired design for electronic structures is converted into a graphic design format and sorted into a pseudo-raster format corresponding to scan lines. A laser or other machining beam is controlled by a separate tracking beam utilizing a mid-objective scanning system. The firing frequency of the machining beam is determined by the position of the tracking beam on a detector, as compared to the scan line data. Accuracy is verified by detection of plume or spectra generated during machining. Evaluation and alignment of the machining and tracking beams is by interferometric methods. The system improves optical performance parameters of telecentricity, angle of scanned beam line, location of line in which the scanned line resides, astigmatism and field curvature.

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Morgan Hill, CA, United States of America

Daniel Guilford Patterson