Sunpower Corporation

Total Marketing Services

Maxeon Solar Pte. Ltd.

Michael Cudzinovic

Thomas Pass

Keith R McIntosh

Richard M Swanson

Joseph Frederick Behnke

William P Mulligan

David D Smith

Richard Hamilton Sewell

David Aaron Randolph Barkhouse

Neil Kaminar

David R Smith

Junbo Wu

Seung Bum Rim

Paul Loscutoff

Peter John Cousins

Taeseok Kim

Michael T Morse

Michel Arsène Olivier Ngamo Toko

Bharatkumar Gamanlal Mehta

Staffan Westerberg

Benjamin I Hsia

Michael C Johnson

Sheng Sun

Robert Woehl

Xiuwen Tu

Xi Zhu

Ben Wahlstrom

Dennis Jason Fuhrman

Todd Richards Johnson

Kyle David Altendorf

Amjad Deyine

Richard Sewell Hamilton

Florito Dennis Tingchuy Vicente

Princess Carmi Tomada

Jemellee Guiao

Rob Rogers

Michel Arséne Olivier Ngamo Toko

Ray-Hon Sun

Approaches for the metallization of solar cells and the resulting solar cells are described. In an example, a method of fabricating a solar cell involves forming a barrier layer on a semiconductor region disposed in or above a substrate. The semiconductor region includes monocrystalline or polycrystalline silicon. The method also involves forming a conductive paste layer on the barrier layer. The method also involves forming a conductive layer from the conductive paste layer. The method also involves forming a contact structure for the semiconductor region of the solar cell, the contact structure including at least the conductive layer.

Metallization of solar cells

Multi-layer sputtered metal seed for solar cell conductive contacts and methods of forming solar cell conductive contacts are described. In an example, a solar cell includes a substrate. A semiconductor region is disposed in or above the substrate. A conductive contact is disposed on the semiconductor region and includes a seed material stack in contact with the semiconductor region. The seed material stack includes a first aluminum layer having a first crystallinity and disposed on the semiconductor layer, and a second aluminum layer having a second crystallinity and disposed on and having an interface with the first aluminum layer. The first crystallinity is different from the second crystallinity.

Multi-layer sputtered metal seed for solar cell conductive contact

Methods of fabricating a solar cell including metallization techniques and resulting solar cells, are described. In an example, a first and second semiconductor regions can be formed in or above a substrate, where a separation region is disposed between the first and second semiconductor regions. A protective region can be formed over the separation region. A first metal layer can be formed over the substrate, where the protective region prevents and/or inhibits damage to the separation region during the formation of the first metal layer. Conductive contacts can be formed over the first and second semiconductor regions.

Protective region for metallization of solar cells

Solar cell contact structures formed from metal paste and methods of forming solar cell contact structures from metal paste are described. In a first example, a solar cell includes a substrate. A semiconductor region is disposed in or above the substrate. A contact structure is disposed on the semiconductor region and includes a conductive layer in contact with the semiconductor region. The conductive layer includes a matrix binder having aluminum/silicon (Al/Si) particles and an inert filler material dispersed therein. In a second example, a solar cell includes a substrate. A semiconductor region is disposed in or above the substrate. A contact structure is disposed on the semiconductor region and includes a conductive layer in contact with the semiconductor region. The conductive layer includes an agent for increasing a hydrophobic characteristic of the conductive layer.

Solar cell contact structures formed from metal paste

A method for forming a contact region for a solar cell is disclosed. The method includes depositing a paste composed of a first metal above a substrate of the solar cell, curing the paste to form a first metal layer, electrolessly plating a second metal layer on the first metal layer and electrolytically plating a third metal layer on the second metal layer, where the second metal layer electrically couples the first metal layer to the third metal layer. The method can further include electrolytically plating a fourth metal layer on the third metal layer.

Methods for electroless plating of a solar cell metallization layer

Enhanced adhesion of seed layers for solar cell conductive contacts and methods of forming solar cell conductive contacts are described. For example, a method of fabricating a solar cell includes forming an adhesion layer above an emitter region of a substrate. A metal seed paste layer is formed on the adhesion layer. The metal seed paste layer and the adhesion layer are annealed to form a conductive layer in contact with the emitter region of the substrate. A conductive contact for the solar cell is formed from the conductive layer.

Enhanced adhesion of seed layer for solar cell conductive contact

Methods for protecting a texturized region and a lightly doped diffusion region of a solar cell to improve solar cell lifetime and efficiency are disclosed. In an embodiment, an example method includes providing a solar cell having a front side which faces the sun during normal operation and a back side opposite the front side, a silicon substrate and where the silicon substrate includes a texturized region and a lightly doped diffusion region. The method includes placing the solar cell on a receiving medium with the front side of the solar cell placed on an upper surface of the receiving medium, where the upper surface of the receiving medium prevents damage to the to the lightly doped diffusion region and damage to the texturized region on the front side of the solar cell during a contact printing process or transferring. In an embodiment, the lightly doped diffusion region has a doping concentration below 1&#xd7;10cmand the receiving medium includes a material having a moh's hardness in the range of 5-10.

Methods for improving solar cell lifetime and efficiency

Fabrication of a solar cell using a printed contact mask. The contact mask may include dots formed by inkjet printing. The dots may be formed in openings between dielectric layers (e.g., polyimide). Intersections of overlapping dots may form gaps that define contact regions. The spacing of the gaps may be dictated by the alignment of nozzles that dispense the dots. Using the dots as a contact mask, an underlying dielectric layer may be etched to form the contact regions through the underlying dielectric layer. Metal contact fingers may be formed over the wafer to form electrical connections to corresponding diffusion regions through the contact regions.

Array of small contacts for solar cell fabrication

A method of fabricating a solar cell is disclosed. The method includes the steps of forming a sacrificial layer on a silicon substrate, forming a doped silicon layer atop the sacrificial substrate, forming a silicon film atop the doped silicon layer, forming a plurality of interdigitated contacts on the silicon film, contacting each of the plurality of interdigitated contacts with a metal contact, and removing the sacrificial layer.

Thin silicon solar cell and method of manufacture

A solar cell that is readily manufactured using processing techniques which are less expensive than microelectronic circuit processing. In preferred embodiments, printing techniques are utilized in selectively forming masks for use in etching of silicon oxide and diffusing dopants and in forming metal contacts to diffused regions. In a preferred embodiment, p-doped regions and n-doped regions are alternately formed in a surface of the wafer through use of masking and etching techniques. Metal contacts are made to the p-regions  and n-regions by first forming a seed layer stack that comprises a first layer such as aluminum that contacts silicon and functions as an infrared reflector, second layer such titanium tungsten that acts as diffusion barrier, and a third layer functions as a plating base. A thick conductive layer such as copper is then plated over the seed layer, and the seed layer between plated lines is removed. A front surface of the wafer is preferably textured by etching or mechanical abrasion with an IR reflection layer provided over the textured surface. A field layer can be provided in the textured surface with the combined effect being a very low surface recombination velocity.

Method of manufacturing solar cell

A substrate patterning method including the steps of spraying ink on a surface of a substrate, the spraying of the ink resulting in an overspray of excess ink past an edge of the substrate; changing a temperature of the excess ink to cause a change in a viscosity of the excess ink; and removing the excess ink having the changed viscosity.

Apparatuses and methods for removal of ink buildup

A solar cell that is readily manufactured using processing techniques which are less expensive than microelectronic circuit processing. In preferred embodiments, printing techniques are utilized in selectively forming masks for use in etching of silicon oxide and diffusing dopants and in forming metal contacts to diffused regions. In a preferred embodiment, p-doped regions and n-doped regions are alternately formed in a surface of the wafer through use of masking and etching techniques. Metal contacts are made to the p-regions and n-regions by first forming a seed layer stack that comprises a first layer such as aluminum that contacts silicon and functions as an infrared reflector, second layer such titanium tungsten that acts as diffusion barrier, and a third layer functions as a plating base. A thick conductive layer such as copper is then plated over the seed layer, and the seed layer between plated lines is removed. A front surface of the wafer is preferably textured by etching or mechanical abrasion with an IR reflection layer provided over the textured surface. A field layer can be provided in the textured surface with the combined effect being a very low surface recombination velocity.

Solar cell and method of manufacture

Growing community of inventors

Sunnyvale, CA, United States of America

Michael Cudzinovic