Patents by Inventor Dharam Pal Gosain

Dharam Pal Gosain 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).

  • Patent number: 6821797
    Abstract: For manufacturing a semiconductor device, such as thin-film solar battery, comprising a base body made of an organic high polymer material, an oxide electrode film and semiconductor thin film each containing at least one kind of group IV elements on the oxide electrode film, one of the semiconductor thin films in contact with the oxide electrode film is stacked by sputtering in a non-reducing atmosphere such as atmosphere not containing hydrogen gas, for example. Thereby, it is ensured that granular products as large as and beyond 3 nm are not contained substantially at the interface between the oxide electrode film and that semiconductor thin film. Therefore, a semiconductor thin film such as amorphous semiconductor thin film can be stacked with enhanced adherence on a plastic substrate having an oxide electrode film like ITO film on its surface.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: November 23, 2004
    Assignee: Sony Corporation
    Inventors: Akio Machida, Dharam Pal Gosain, Takashi Noguchi, Setsuo Usui
  • Publication number: 20040209447
    Abstract: Disclosed are a method of producing a crystalline semiconductor material capable of improving the crystallinity and a method of fabricating a semiconductor device using the crystalline semiconductor material. An amorphous film is uniformly irradiated with a pulse laser beam (energy beam) emitted from an XeCl excimer laser by 150 times so as to heat the amorphous film at such a temperature as to partially melt crystal grains having the {100} orientations with respect to the vertical direction of a substrate and melt amorphous film or crystal grains having face orientations other than the {100} orientations. Silicon crystals having the {100} orientations newly occur between a silicon oxide film and liquid-phase silicon and are bonded to each other at random, to newly form crystal grains having the {100} orientations.
    Type: Application
    Filed: August 21, 2003
    Publication date: October 21, 2004
    Inventors: Dharam Pal Gosain, Akio Machida, Kazushi Nakano, Toshio Fujino, Junichi Sato
  • Patent number: 6806169
    Abstract: In a manufacturing method of a thin-film transistor having a polycrystalline Si film as its active region, an amorphous-phase Si film is first formed, and pulse laser beams are irradiated to crystallize the Si film and thereby form a polycrystalline Si film. After electrodes are made on a source region and a drain region, a SiNx film as a hydrogen-containing film is formed on the entire surface. By irradiating pulse laser beams to heat the SiNx film, hydrogen in the SiNx film is diffused into the polycrystalline Si film to hydrogenate it and reduce the trap density along crystal grain boundaries in the polycrystalline Si film.
    Type: Grant
    Filed: July 28, 1999
    Date of Patent: October 19, 2004
    Assignee: Sony Corporation
    Inventors: Dharam Pal Gosain, Setsuo Usui
  • Patent number: 6794277
    Abstract: A lower concentration impurity diffusion region can be formed under excellent control, even when a low heat-resistant substrate is used. At the time of doping a semiconductor layer, a mask such as sidewalls (24) where an energy beam passes through, is formed on a part of a surface of a semiconductor layer (21), dopant ions (25) are adsorbed on the surface of the semiconductor layer (21) except a region in which the mask is formed, and an energy beam EBL is irradiated onto the semiconductor layer (21) having the formed mask to introduce the dopant ions into the semiconductor layer (21). In the lower part of the mask such sidewalls (24), diffusion in transverse direction occurs and lower concentration impurity diffusion regions can be formed in excellent reproducibility under excellent control.
    Type: Grant
    Filed: October 23, 2002
    Date of Patent: September 21, 2004
    Assignee: Sony Corporation
    Inventors: Akio Machida, Setsuo Usui, Dharam Pal Gosain
  • Patent number: 6794673
    Abstract: An amorphous silicon thin film includes a plastic substrate as a base, and insulating layers are formed thereon each radiated with a pulse laser beam which removes volatile contaminants like a resist as a pretreatment. A protective layer including a gas barrier layer and a refractory buffer layer is formed on the substrate. Gas penetration from the substrate to the amorphous silicon film is thereby prevented. Conduction of heat produced by energy beam radiation to the substrate is prevented as well. it is possible to increase energy intensity of energy beam radiated for the polycrystallization of the amorphous silicon film to the optimal value for perfect polycrystallization.
    Type: Grant
    Filed: December 11, 2001
    Date of Patent: September 21, 2004
    Assignee: Sony Corporation
    Inventors: Dharam Pal Gosain, Jonathan Westwater, Miyako Nakagoe, Setsuo Usui, Kazumasa Nomoto
  • Publication number: 20040157470
    Abstract: The invention provides a functional device having no cracks and capable of delivering good functional characteristics and a method of manufacturing the same. A functional layer (14) is formed by crystallizing an amorphous silicon layer as a precursor layer by laser beam irradiation. A laser beam irradiation conducts heat up to a substrate (11) to cause it to try to expand; a stress to be produced by the difference in thermal expansion coefficient between the substrate (11) and the functional layer (14) is shut off by an organic polymer layer (12) lower in thermal expansion coefficient than the substrate (ii), thereby causing no cracks nor separations in the functional layer (14). The organic polymer layer (12) is preferably made of an acrylic resin, an epoxy resin, or a polymer material containing these that is deformed by an optical or thermal process to undergo a three-dimensional condensation polymerization, for higher compactness and hardness.
    Type: Application
    Filed: November 24, 2003
    Publication date: August 12, 2004
    Inventors: Akio Machida, Dharam Pal Gosain, Setsuo Usui
  • Publication number: 20040110343
    Abstract: A low concentration impurity diffusion region is formed with good controllability even in case of using a low heat resistant substrate. When doping a semiconductor layer, after forming the semiconductor layer on the substrate, the amount of the dopant ion adsorbed on a surface of the semiconductor layer is controlled by introducing hydrogen gas at the time of plasma irradiation and activating the adsorbed dopant ion in the semiconductor layer by an excimer laser.
    Type: Application
    Filed: December 15, 2003
    Publication date: June 10, 2004
    Inventors: Akio Machida, Setsuo Usui, Dharam Pal Gosain
  • Patent number: 6716664
    Abstract: A functional device free from cracking and having excellent functional characteristics, and a method of manufacturing the same are disclosed. A low-temperature softening layer (12) and a heat-resistant layer (13) are formed in this order on a substrate (11) made of an organic material such as polyethylene terephthalate, and a functional layer (14) made of polysilicon is formed thereon. The functional layer (14) is formed by crystallizing an amorphous silicon layer, which is a precursor layer, with laser beam irradiation. When a laser beam is applied, heat is transmitted to the substrate (11) and the substrate (11) tends to expand. However, a stress caused by a difference in a thermal expansion coefficient between the substrate (11) and the functional layer (14) is absorbed by the low-temperature softening layer (12), so that no cracks and peeling occurs in the functional layer (14). The low-temperature softening layer (12) is preferably made of a polymeric material containing an acrylic resin.
    Type: Grant
    Filed: March 20, 2003
    Date of Patent: April 6, 2004
    Assignee: Sony Corporation
    Inventors: Akio Machida, Dharam Pal Gosain, Setsuo Usui
  • Publication number: 20040060592
    Abstract: For manufacturing a semiconductor device, such as thin-film solar battery, comprising a base body made of an organic high polymer material, an oxide electrode film and semiconductor thin film each containing at least one kind of group IV elements on the oxide electrode film, one of the semiconductor thin films in contact with the oxide electrode film is stacked by sputtering in a non-reducing atmosphere such as atmosphere not containing hydrogen gas, for example. Thereby, it is ensured that granular products as large as and beyond 3 nm are not contained substantially at the interface between the oxide electrode film and that semiconductor thin film. Therefore, a semiconductor thin film such as amorphous semiconductor thin film can be stacked with enhanced adherence on a plastic substrate having an oxide electrode film like ITO film on its surface.
    Type: Application
    Filed: September 26, 2003
    Publication date: April 1, 2004
    Inventors: Akio Machida, Dharam Pal Gosain, Takashi Noguchi, Setsuo Usui
  • Patent number: 6661027
    Abstract: For manufacturing a semiconductor device, such as thin-film solar battery, comprising a base body made of an organic high polymer material, an oxide electrode film and semiconductor thin film each containing at least one kind of group IV elements on the oxide electrode film, one of the semiconductor thin films in contact with the oxide electrode film is stacked by sputtering in a non-reducing atmosphere such as atmosphere not containing hydrogen gas, for example. Thereby, it is ensured that granular products as large as and beyond 3 nm are not contained substantially at the interface between the oxide electrode film and that semiconductor thin film. Therefore, a semiconductor thin film such as amorphous semiconductor thin film can be stacked with enhanced adherence on a plastic substrate having an oxide electrode film like ITO film on its surface.
    Type: Grant
    Filed: November 22, 2000
    Date of Patent: December 9, 2003
    Assignee: Sony Corporation
    Inventors: Akio Machida, Dharam Pal Gosain, Takashi Noguchi, Setsuo Usui
  • Patent number: 6645837
    Abstract: A polycrystalline silicon layer is formed on a substrate. An insulating layer and a gate electrode are formed on the polycrystalline silicon layer. Then, a channel region, a source region and a drain region are formed in a self-aligned manner by doping an impurity in the polycrystalline silicon layer using the gate electrode as a mask. Then, an energy absorption layer is formed so as to cover the entire substrate and a pulsed laser beam is irradiated from the energy absorption layer side. The energy of the pulsed laser beam is almost completely absorbed in the energy absorption layer and a heat treatment is indirectly performed on the underlying layers by radiating the heat. In other words, activation of the impurity and removal of defects in the insulating layer are performed at the same time without damaging the substrate by the heat.
    Type: Grant
    Filed: May 31, 2001
    Date of Patent: November 11, 2003
    Assignee: Sony Corporation
    Inventors: Dharam Pal Gosain, Kazumasa Nomoto, Akio Machida, Miyako Nakagoe, Setsuo Usui
  • Publication number: 20030207507
    Abstract: To enable radiating an optimum energy beam depending upon the structure of a substrate (whether a metallic film is formed or not) when an amorphous semiconductor film is crystallized and uniformly crystallizing the overall film, first, a photoresist film and the area of an N− doped amorphous silicon film on the photoresist film are selectively removed by a lift-off method. Hereby, the amorphous silicon film is thicker in an area except an area over a metallic film (a gate electrode) than in the area over the metallic film In this state, a laser beam is radiated. The N− doped amorphous silicon film and an amorphous silicon film are melted by radiating a laser beam and afterward, melted areas are crystallized by cooling them to room temperature.
    Type: Application
    Filed: June 2, 2003
    Publication date: November 6, 2003
    Inventors: Dharam Pal Gosain, Jonathan Westwater, Miyako Nakagoe, Setsuo Usui
  • Publication number: 20030173601
    Abstract: A functional device free from cracking and having excellent functional characteristics, and a method of manufacturing the same are disclosed. A low-temperature softening layer (12) and a heat-resistant layer (13) are formed in this order on a substrate (11) made of an organic material such as polyethylene terephthalate, and a functional layer (14) made of polysilicon is formed thereon. The functional layer (14) is formed by crystallizing an amorphous silicon layer, which is a precursor layer, with laser beam irradiation. When a laser beam is applied, heat is transmitted to the substrate (11) and the substrate (11) tends to expand. However, a stress caused by a difference in a thermal expansion coefficient between the substrate (11) and the functional layer (14) is absorbed by the low-temperature softening layer (12), so that no cracks and peeling occurs in the functional layer (14). The low-temperature softening layer (12) is preferably made of a polymeric material containing an acrylic resin.
    Type: Application
    Filed: March 20, 2003
    Publication date: September 18, 2003
    Inventors: Akio Machida, Dharam Pal Gosain, Setsuo Usui
  • Patent number: 6570223
    Abstract: A functional device and method of manufacturing the same are disclosed. A low-temperature softening layer and a heat-resistant layer are formed in this order on a substrate made of organic material such as polyethylene terephthalate, and a functional layer made of polysilicon is formed thereon. The functional layer is formed by crystallizing an amorphous silicon layer (precursor layer), with laser beam irradiation. When a laser beam is applied, heat causes the substrate to expand. However, stress caused by a difference in a thermal expansion coefficient between the substrate and the functional layer is absorbed by the low-temperature softening layer, so that no cracks and peeling occurs in the functional layer. The low-temperature softening layer is preferably made of a polymeric material containing acrylic resin. By properly interposing a metal layer and a heat-resistant layer between the substrate and the functional layer, a laser beam of higher intensity can be irradiated.
    Type: Grant
    Filed: October 2, 2001
    Date of Patent: May 27, 2003
    Assignee: Sony Corporation
    Inventors: Akio Machida, Dharam Pal Gosain, Setsuo Usui
  • Publication number: 20030077886
    Abstract: A lower concentration impurity diffusion region can be formed under excellent control, even when a low heat-resistant substrate is used. At the time of doping a semiconductor layer, a mask such as sidewalls (24) where an energy beam passes through, is formed on a part of a surface of a semiconductor layer (21), dopant ions (25) are adsorbed on the surface of the semiconductor layer (21) except a region in which the mask is formed, and an energy beam EBL is irradiated onto the semiconductor layer (21) having the formed mask to introduce the dopant ions into the semiconductor layer (21). In the lower part of the mask such sidewalls (24), diffusion in transverse direction occurs and lower concentration impurity diffusion regions can be formed in excellent reproducibility under excellent control.
    Type: Application
    Filed: October 23, 2002
    Publication date: April 24, 2003
    Inventors: Akio Machida, Setsuo Usui, Dharam Pal Gosain
  • Patent number: 6461917
    Abstract: A memory device, a manufacturing method thereof, and an integrated circuit thereof are provided for storing information over a long period of time even if the memory device is manufactured at low temperatures. On a substrate made of glass, etc., a memory transistor and a selection transistor are formed, with a silicon nitride film and a silicon dioxide film in between. The memory transistor and the selection transistor are connected in series at a second impurity region. The conduction region for memory of the memory transistor is made of non-single crystal silicon and a storage region comprises a plurality of dispersed particulates made of non-single crystal silicon. Therefore, electrical charges can be stored partially if a tunnel insulating film has any defects. The tunnel insulating film is formed by exposing the surface of the conduction region for memory to the ionized gas containing oxygen atoms.
    Type: Grant
    Filed: June 25, 2001
    Date of Patent: October 8, 2002
    Assignee: Sony Corporation
    Inventors: Kazumasa Nomoto, Dharam Pal Gosain, Setsuo Usui, Takashi Noguchi
  • Patent number: 6410412
    Abstract: Methods for fabricating memory devices having a multi-dot floating gate ensuring a desirable crystallization of a semiconductor film without ruining the flatness of the surface of the polycrystallized silicon layer and a tunnel oxide film, allowing desirable semiconductor dots to be produced, and allowing production of the memory devices having a multi-dot floating gate with ease and at low costs even when a substrate is made of glass or plastic.
    Type: Grant
    Filed: September 15, 2000
    Date of Patent: June 25, 2002
    Assignee: Sony Corporation
    Inventors: Kenichi Taira, Noriyuki Kawashima, Takashi Noguchi, Dharam Pal Gosain, Setsuo Usui
  • Publication number: 20020068390
    Abstract: A method is provided for forming a semiconductor thin film which is free from damage to the film with radiation of a pulse laser beam with the optimum energy value for perfect polycrystallization. For forming an amorphous silicon thin film, a surface of a plastic substrate as a base and insulating layers are each radiated with a pulse laser beam for removing volatile contaminants like a resist as a pretreatment. Damage to the film caused by a gas emitted from the base substrate and the insulating layers resulting from volatile contaminants is thus prevented. A protective layer including a gas barrier layer and a refractory buffer layer is formed on the substrate. Gas penetration from the substrate to the amorphous silicon film is thereby prevented. Conduction of heat produced by energy beam radiation to the substrate is prevented as well.
    Type: Application
    Filed: December 11, 2001
    Publication date: June 6, 2002
    Inventors: Dharam Pal Gosain, Jonathan Westwater, Miyako Nakagoe, Setsuo Usui, Kazumasa Nomoto
  • Publication number: 20020048869
    Abstract: A method is provided for forming a semiconductor thin film which is free from damage to the film with radiation of a pulse laser beam with the optimum energy value for perfect polycrystallization. For forming an amorphous silicon thin film, a surface of a plastic substrate as a base and insulating layers are each radiated with a pulse laser beam for removing volatile contaminants like a resist as a pretreatment. Damage to the film caused by a gas emitted from the base substrate and the insulating layers resulting from volatile contaminants is thus prevented. A protective layer including a gas barrier layer and a refractory buffer layer is formed on the substrate. Gas penetration from the substrate to the amorphous silicon film is thereby prevented. Conduction of heat produced by energy beam radiation to the substrate is prevented as well.
    Type: Application
    Filed: July 16, 1998
    Publication date: April 25, 2002
    Inventors: DHARAM PAL GOSAIN, JONATHAN WESTWATER, MIYAKO NAKAGOE, SETSUO USUI, KAZUMASA NOMOTO
  • Patent number: 6376290
    Abstract: A method is provided for forming a semiconductor thin film which is free from damage to the film with radiation of a pulse laser beam with the optimum energy value for perfect polycrystallization. For forming an amorphous silicon thin film, a surface of a plastic substrate as a base and insulating layers are each radiated with a pulse laser beam for removing volatile contaminants like a resist as a pretreatment. Damage to the film caused by a gas emitted from the base substrate and the insulating layers resulting from volatile contaminants is thus prevented. A protective layer including a gas barrier layer and a refractory buffer layer is formed on the substrate. Gas penetration from the substrate to the amorphous silicon film is thereby prevented. Conduction of heat produced by energy beam radiation to the substrate is prevented as well.
    Type: Grant
    Filed: July 16, 1998
    Date of Patent: April 23, 2002
    Assignee: Sony Corporation
    Inventors: Dharam Pal Gosain, Jonathan Westwater, Miyako Nakagoe, Setsuo Usui, Kazumasa Nomoto