Patents by Inventor Eiji Higa

Eiji Higa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20100093153
    Abstract: To prevent, in the case of irradiating a single crystal semiconductor layer with a laser beam, an impurity element from being taken into the single crystal semiconductor layer at the time of laser irradiation.
    Type: Application
    Filed: October 8, 2009
    Publication date: April 15, 2010
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Masaki Koyama, Junpei Momo, Eiji Higa, Hiroaki Honda, Tamae Moriwaka, Akihisa Shimomura
  • Publication number: 20100087047
    Abstract: To increase adhesion between a single crystal semiconductor layer and a base substrate and to reduce bonding defects therebetween. To perform radical treatment on a surface of a semiconductor substrate to form a first insulating film on the semiconductor substrate; irradiate the semiconductor substrate with accelerated ions through the first insulating film to form an embrittlement region in the semiconductor substrate; form a second insulating film on the first insulating film; perform heat treatment after bonding a surface of the second insulating film and a surface of the base substrate to perform separation along the embrittlement region so that a semiconductor layer is formed over the base substrate with the first and second insulating films interposed therebetween; etch the semiconductor layer; and irradiate the semiconductor layer on which the etching is performed with a laser beam.
    Type: Application
    Filed: September 29, 2009
    Publication date: April 8, 2010
    Inventors: Akihisa Shimomura, Masaki Koyama, Eiji Higa
  • Publication number: 20090111244
    Abstract: A single crystal semiconductor substrate is irradiated with ions that are generated by exciting a hydrogen gas and are accelerated with an ion doping apparatus, thereby forming a damaged region that contains a large amount of hydrogen. After the single crystal semiconductor substrate and a supporting substrate are bonded, the single crystal semiconductor substrate is heated to be separated along the damaged region. While a single crystal semiconductor layer separated from the single crystal semiconductor substrate is heated, this single crystal semiconductor layer is irradiated with a laser beam. The single crystal semiconductor layer undergoes re-single-crystallization by being melted through laser beam irradiation, thereby recovering its crystallinity and planarizing the surface of the single crystal semiconductor layer.
    Type: Application
    Filed: October 7, 2008
    Publication date: April 30, 2009
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Shunpei YAMAZAKI, Junpei MOMO, Fumito ISAKA, Eiji HIGA, Masaki KOYAMA, Akihisa SHIMOMURA
  • Publication number: 20090072343
    Abstract: A high-performance semiconductor device using an SOI substrate in which a low-heat-resistance substrate is used as a base substrate. Further, a high-performance semiconductor device formed without using chemical polishing. Further, an electronic device using the semiconductor device. An insulating layer over an insulating substrate, a bonding layer over the insulating layer, and a single-crystal semiconductor layer over the bonding layer are included, and the arithmetic-mean roughness of roughness in an upper surface of the single-crystal semiconductor layer is greater than or equal to 1 nm and less than or equal to 7 nm. Alternatively, the root-mean-square roughness of the roughness may be greater than or equal to 1 nm and less than or equal to 10 nm. Alternatively, a maximum difference in height of the roughness may be greater than or equal to 5 nm and less than or equal to 250 nm.
    Type: Application
    Filed: September 10, 2008
    Publication date: March 19, 2009
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Hideto OHNUMA, Yoichi IIKUBO, Yoshiaki YAMAMOTO, Kenichiro MAKINO, Akihisa SHIMOMURA, Eiji HIGA, Tatsuya MIZOI, Yoji NAGANO, Fumito ISAKA, Tetsuya KAKEHATA, Shunpei YAMAZAKI
  • Publication number: 20080286952
    Abstract: A manufacturing method of an SOI substrate which possesses a base substrate having low heat resistance and a very thin semiconductor layer having high planarity is demonstrated. The method includes: implanting hydrogen ions into a semiconductor substrate to form an ion implantation layer; bonding the semiconductor substrate and a base substrate such as a glass substrate, placing a bonding layer therebetween; heating the substrates bonded to each other to separate the semiconductor substrate from the base substrate, leaving a thin semiconductor layer over the base substrate; irradiating the surface of the thin semiconductor layer with laser light to improve the planarity and recover the crystallinity of the thin semiconductor layer; and thinning the thin semiconductor layer. This method allows the formation of an SOI substrate which has a single-crystalline semiconductor layer with a thickness of 100 nm or less over a base substrate.
    Type: Application
    Filed: March 28, 2008
    Publication date: November 20, 2008
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Hidekazu Miyairi, Akihisa Shimomura, Tatsuya Mizoi, Eiji Higa, Yoji Nagano
  • Publication number: 20080261376
    Abstract: To provide an SOI substrate with an SOI layer that can be put into practical use, even when a substrate with a low allowable temperature limit such as a glass substrate is used, and to provide a semiconductor substrate formed using such an SOI substrate. In order to bond a single-crystalline semiconductor substrate to a base substrate such as a glass substrate, a silicon oxide film formed by CVD with organic silane as a source material is used as a bonding layer, for example. Accordingly, an SOI substrate with a strong bond portion can be formed even when a substrate with an allowable temperature limit of less than or equal to 700° C. such as a glass substrate is used. A semiconductor layer separated from the single-crystalline semiconductor substrate is irradiated with a laser beam so that the surface of the semiconductor layer is planarized and the crystallinity thereof is recovered.
    Type: Application
    Filed: March 31, 2008
    Publication date: October 23, 2008
    Applicant: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Eiji Higa, Yoji Nagano, Tatsuya Mizoi, Akihisa Shimomura
  • Publication number: 20080070393
    Abstract: In a manufacturing process of a semiconductor device, a manufacturing technique for reducing the number of lithography processes that use a photoresist and simplifying the process is provided, which improves throughput. An etching mask for forming a pattern of a layer to be processed such as a conductive layer or a semiconductor layer is manufactured without using a lithography technique that uses a photoresist. The etching mask is formed of a light absorption layer including a material which absorbs a laser beam. The mask is formed by irradiating the light absorption layer with a laser beam through a photomask and utilizing laser ablation by energy of the laser beam absorbed by the light absorption layer.
    Type: Application
    Filed: August 15, 2007
    Publication date: March 20, 2008
    Inventors: Hidekazu Miyairi, Yasuhiro Jinbo, Eiji Higa, Shunpei Yamazaki
  • Publication number: 20080050895
    Abstract: In a manufacturing process of a semiconductor device, a manufacturing technique for reducing the number of lithography processes using a photoresist and simplifying the process is provided, and the throughput is improved. An etching mask for forming a pattern of a layer to be processed such as a conductive layer or a semiconductor layer is manufactured without using a lithography technique that uses a photoresist. The etching mask is formed of a stacked layer structure of a light absorption layer and an insulating layer utilizing laser ablation by laser beam irradiation through a photomask.
    Type: Application
    Filed: August 17, 2007
    Publication date: February 28, 2008
    Inventors: Hidekazu Miyairi, Eiji Higa
  • Publication number: 20080026543
    Abstract: A method of forming a semiconductor device is provided, including a step of forming a layer which absorbs light over one face of a first substrate, a step of providing a second substrate over the layer which absorbs light, a step of providing a mask to oppose the other face of the first substrate, and a step of transferring the part of the layer which absorbs light to the second substrate by irradiating the layer which absorbs light with a laser beam through the mask.
    Type: Application
    Filed: July 25, 2007
    Publication date: January 31, 2008
    Inventors: Hidekazu Miyairi, Hironobu Shoji, Akihisa Shimomura, Eiji Higa, Tomoaki Moriwaka, Shunpei Yamazaki