# US 5,348,589 A · Solar cell and method of forming the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,348,589 A - Document ID: US5348589A - Status: Granted - Kind: A - Application number: 07/996,399 - Filed: 1992-12-23 - Granted: 1994-09-20 - Earliest claimed: 1991-12-27 - Assignees: Semiconductor Energy Laboratory Co., Ltd. - Inventors: Yasuyuki Arai; Setsuo Nakajima - Web page: https://patentgrep.com/patent/US5348589A ## CPC - H10F 71/103: {including only Group IV materials} - H10F 19/31: having multiple laterally adjacent thin-film photovoltaic cells deposited on the same substrate - H10F 19/33: Patterning processes to connect the photovoltaic cells, e.g. laser cutting of conductive or active layers - H10F 19/35: Structures for the connecting of adjacent photovoltaic cells, e.g. interconnections or insulating spacers - H10F 77/1692: {the films including only Group IV materials} - H10F 77/48: Back surface reflectors [BSR] - Y02E 10/52: PV systems with concentrators - Y02P 70/50: Manufacturing or production processes characterised by the final manufactured product - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract A manufacturing method and an improved structure for solar cells are described. A transparent conductive film and a photoelectric conversion layer are laminated on a flexible transparent substrate, and thereafter the laminate is divided by a first groove formed by laser scribing. A second groove is also formed at the same time in parallel to the first groove. The first groove is filled with an insulating material. An insulating strip is formed in parallel with the first groove. A reflective conductive film is then coated over the structure in order to make electric contact with the transparent conductive film. Finally, the reflective conductive film is divided by a third groove formed along the insulating strip. ## Claims ### Claim 1 A method of forming a photovoltaic cell, comprising a step of sequentially forming a transparent first conductive film and a photoelectric conversion film on a transparent substrate, a step of forming a first groove and a second groove in order to divide said transparent first conductive film into a first transparent electrode and a second transparent electrode and in order to divide said photoelectric conversion film into a first photoelectric conversion region on said first transparent electrode and a second photoelectric conversion region on said second transparent electrode, a step of filling said first groove with a first insulator material and a second insulator located on said second photoelectric conversion region adjacent said second groove, a step of forming a second conductive film on said photoelectric conversion film over said first insulator and said second insulator in order to fill said second groove, and a step of laser scribing said second conductive film in order to form a third groove extending down to said second insulator and thereby dividing said second conductive film into first and second rear electrodes, whereby said first rear electrode is provided on said first photoelectric conversion region and is connected to said second transparent electrode through the filled second groove, and said second rear electrode is provided on said second photoelectric conversion region and is isolated from said first rear electrode by said third groove. ### Claim 2 (depends on 1) The method of claim 1, wherein said second conductive film substantially covers said photoelectric conversion film. ### Claim 3 A method of forming a photovoltaic cell comprising: forming a first conductive film on a substrate; forming a photoelectric conversion layer on said first conductive film; forming a first groove through said photoelectric conversion layer and said first conductive film in order to divide said first conductive film; forming an opening through said photoelectric conversion layer and reaching to said first conductive film; forming a first insulating strip to fill said first groove; forming a second conductive film on said photoelectric conversion layer over said first insulating strip and making electrical contact with said first conductive film through said opening such that said second conductive film serially interconnects said first conductive film with another photovoltaic cell; and forming a second groove through said second conductive film in order to electrically divide said second conductive film, said opening being located between said first groove and said second groove. ### Claim 4 (depends on 2) The method of claim 2, wherein said opening is formed as a third groove extending substantially in parallel to said first groove. ### Claim 5 (depends on 3) The method of claim 3, further comprising a step of forming a second insulating strip between said photoelectric conversion layer and said second conductive film and extending in parallel to said first groove, said second groove being formed along and just above said second insulating strip and reaching to said second insulating strip. ### Claim 6 (depends on 3) The method of claim 3, wherein said second conductive film substantially covers said photoelectric conversion film. ### Claim 7 A method of forming a photovoltaic cell comprising: forming a first conductive film on a substrate; forming a photoelectric conversion layer on said first conductive film; forming a first groove through said photoelectric conversion layer and said first conductive film in order to electrically divide said first conductive film and said photoelectric conversion layer; forming a first insulating strip to fill said first groove; forming a second insulating strip on said photoelectric conversion layer and extending substantially in parallel to said first groove; forming an opening through said photoelectric conversion layer between said first groove and said insulating strip and reaching to said first conductive film; forming a second conductive film on said photoelectric conversion layer over said insulating strip in electrical contact with said first conductive film through said opening such that said second conductive film serially interconnects said first conductive film with another photovoltaic cell; and forming a second groove through said second conductive film along and reaching to said insulating strip in order to electrically divide said second conductive film. ### Claim 8 (depends on 7) The method of claim 7, wherein said second conductive film substantially covers said photoelectric conversion film. ### Claim 9 In a photovoltaic cell having a plurality of photoelectric conversion units connected in series on a substrate, each photoelectric conversion unit comprising a laminate of a first electrode, a photoelectric conversion layer, and a second electrode, wherein a first unit of said photoelectric conversion units is connected with a second unit of said photoelectric conversion units adjacent to said first unit through a connection structure having a first groove and a second groove formed in a laminate of said first electrode and said photoelectric conversion layer and a third groove formed through said second electrode, said first groove is filled with an insulator, said second groove is filled with a conductive material through which the first electrode of said second unit is connected to the second electrode of said first unit, the second electrode of said second unit is separated from the second electrode of said first unit by said third groove, and said third groove is located on an insulator formed on said photoelectric conversion layer. ### Claim 10 (depends on 9) The photovoltaic cell of claim 9, wherein said conductive material substantially covers said photoelectric conversion layer and extends over said insulators. ### Claim 11 A photovoltaic cell comprising: an insulating substrate; a first conductive film formed on said substrate; a photoelectric conversion layer formed on said first conductive film; a first groove formed through said photoelectric conversion layer and said first conductive film in order to electrically divide said first conductive film; a first insulating strip filling said first groove; an opening formed through said photoelectric conversion layer and reaching to said first conductive film; a second conductive film formed on said photoelectric conversion layer in electrical contact with said first conductive film through said opening to serially interconnect said first conductive film with another photovoltaic cell; and a second groove formed through said second conductive film in order to electrically divide said second conductive film, said opening being located between said first groove and said second groove. ### Claim 12 (depends on 11) The photovoltaic cell of claim 11, wherein said opening is a third groove extending substantially, parallel to said first groove. ### Claim 13 (depends on 11) The photovoltaic cell of claim 11, further comprising a second insulating strip formed between said photoelectric conversion layer and said second conductive film and extending in parallel to said first groove, said second groove being formed along and just above to said second insulating strip and reaching to said second insulating strip. ### Claim 14 (depends on 11) The photovoltaic cell of claim 11, wherein said substrate is transparent. ### Claim 15 (depends on 11) The photovoltaic cell of claim 11, wherein said substrate is flexible. ### Claim 16 (depends on 11) The photovoltaic cell claim 11, wherein said substrate is made of a plastic film. ### Claim 17 (depends on 16) The photovoltaic cell of claim 16, wherein said substrate is made of polyethylene terephthalate. ### Claim 18 (depends on 11) The photovoltaic cell of claim 11, wherein said photoelectric conversion layer comprises amorphous semiconductor films forming a PIN junction. ### Claim 19 (depends on 11) The photovoltaic cell of claim 11, wherein said second conductive film substantially covers said photoelectric conversion layer and extends over said first insulating strip. ### Claim 20 A photovoltaic cell comprising: an insulating substrate; a first conductive film formed on said substrate; a photoelectric conversion layer formed on said first conductive film; a first groove formed through said photoelectric conversion layer and said first conductive film in order to electrically divide said first conductive film and said photoelectric conversion layer; an insulating strip formed on said photoelectric conversion layer and extending substantially in parallel to said first groove; an opening formed through said photoelectric conversion layer between said first groove and said insulating strip and reaching to said first conductive film; a second conductive film formed on said photoelectric conversion layer over said insulating strip in electrical contact with said first conductive film through said opening to serially interconnect said first conductive film with another photovoltaic cell; and a second groove formed through said second conductive film along and reaching to said insulating strip in order to electrically divide said second conductive film. ### Claim 21 (depends on 20) The photovoltaic cell of claim 20, wherein said insulating strip is maple of an epoxy resin. ### Claim 22 (depends on 20) The photovoltaic cell of claim 20, wherein said substrate is transparent. ### Claim 23 (depends on 20) The photovoltaic cell of claim 20, wherein said substrate is flexible. ### Claim 24 (depends on 20) The photovoltaic cell of claim 20, wherein said substrate is made of a plastic film. ### Claim 25 (depends on 24) The photovoltaic cell of claim 24, wherein said substrate is made of polyethylene terephthalate. ### Claim 26 (depends on 20) The photovoltaic cell of claim 20, wherein said photoelectric conversion layer comprises amorphous semiconductor films forming a PIN junction.