Patents by Inventor Sierra HOFF
Sierra HOFF 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: 10316431Abstract: The present invention provides a method of growing an ingot of group III nitride. Group III nitride crystals such as GaN are grown by the ammonothermal method on both sides of a seed to form an ingot and the ingot is sliced into wafers. The wafer including the first-generation seed is sliced thicker than the other wafers so that the wafer including the first-generation seed does not break. The wafer including the first-generation seed crystal can be used as a seed for the next ammonothermal growth.Type: GrantFiled: October 20, 2015Date of Patent: June 11, 2019Assignees: SixPoint Materials, Inc., Seoul Semiconductor Co., Ltd.Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Patent number: 9543393Abstract: The present invention discloses a group III nitride wafer such as GaN, AlN, InN and their alloys having one surface visually distinguishable from the other surface. After slicing of the wafer from a bulk crystal of group III nitride with a mechanical method such as multiple wire saw, the wafer is chemically etched so that one surface of the wafer is visually distinguishable from the other surface. The present invention also discloses a method of producing such wafers.Type: GrantFiled: March 15, 2013Date of Patent: January 10, 2017Assignees: SixPoint Materials, Inc., Seoul Semiconductor Co., Ltd.Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Patent number: 9518340Abstract: The present invention provides a method of growing an ingot of group III nitride. Group III nitride crystals such as GaN are grown by the ammonothermal method on both sides of a seed to form an ingot and the ingot is sliced into wafers. The wafer including the first-generation seed is sliced thicker than the other wafers so that the wafer including the first-generation seed does not break. The wafer including the first-generation seed crystal can be used as a seed for the next ammonothermal growth.Type: GrantFiled: March 15, 2013Date of Patent: December 13, 2016Assignees: SixPoint Materials, Inc., Seoul Semiconductor Co., Ltd.Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Patent number: 9452495Abstract: The present invention discloses a new tool to slice crystal ingots by using laser beams. Ingot crystals of III-nitride such as GaN are immersed in alkali solutions and irradiated with scanned lines of laser beams to slice wafers out of the ingots. The method is expected to achieve approximately one order of magnitude smaller slicing loss with minimized slicing damage.Type: GrantFiled: July 6, 2012Date of Patent: September 27, 2016Assignee: SixPoint Materials, Inc.Inventors: Tadao Hashimoto, Sierra Hoff
-
Patent number: 9435051Abstract: The present invention discloses a semi-insulating wafer of GaxAlyIn1-x-yN (0?x?1, 0?x+y?1) which is doped with bismuth (Bi). The semi-insulating wafer has the resistivity of 104 ohm-cm or more. Although it is very difficult to obtain a single crystal ingot of group III nitride, the ammonothermal method can grow highly-oriented poly or single crystal ingot of group III nitride having the density of dislocations/grain boundaries less than 105 cm?2. The invention also disclose the method of fabricating the semi-insulating group III nitride bulk crystals and wafers.Type: GrantFiled: December 28, 2015Date of Patent: September 6, 2016Assignees: SixPoint Materials, Inc., Seoul Semiconductor Co., Ltd.Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Publication number: 20160130720Abstract: The present invention discloses a semi-insulating wafer of GaxAlyIn1-x-yN (0?x?1, 0?x+y?1) which is doped with bismuth (Bi). The semi-insulating wafer has the resistivity of 104 ohm-cm or more. Although it is very difficult to obtain a single crystal ingot of group III nitride, the ammonothermal method can grow highly-oriented poly or single crystal ingot of group III nitride having the density of dislocations/grain boundaries less than 105 cm?2. The invention also disclose the method of fabricating the semi-insulating group III nitride bulk crystals and wafers.Type: ApplicationFiled: December 28, 2015Publication date: May 12, 2016Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Publication number: 20160040318Abstract: The present invention provides a method of growing an ingot of group III nitride. Group III nitride crystals such as GaN are grown by the ammonothermal method on both sides of a seed to form an ingot and the ingot is sliced into wafers. The wafer including the first-generation seed is sliced thicker than the other wafers so that the wafer including the first-generation seed does not break. The wafer including the first-generation seed crystal can be used as a seed for the next ammonothermal growth.Type: ApplicationFiled: October 20, 2015Publication date: February 11, 2016Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Patent number: 9255342Abstract: The present invention discloses a semi-insulating wafer of GaxAlyIn1-x-yN (0?x?1, 0?x+y?1) which is doped with bismuth (Bi). The semi-insulating wafer has the resistivity of 104 ohm-cm or more. Although it is very difficult to obtain a single crystal ingot of group III nitride, the ammonothermal method can grow highly-oriented poly or single crystal ingot of group III nitride having the density of dislocations/grain boundaries less than 105 cm?2. The invention also disclose the method of fabricating the semi-insulating group III nitride bulk crystals and wafers.Type: GrantFiled: February 28, 2013Date of Patent: February 9, 2016Assignees: SixPoint Materials, Inc., Seoul Semiconductor Co., Ltd.Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Patent number: 9202872Abstract: The present invention provides a method of growing an ingot of group III nitride. Group III nitride crystals such as GaN are grown by the ammonothermal method on both sides of a seed to form an ingot and the ingot is sliced into wafers. The wafer including the first-generation seed is sliced thicker than the other wafers so that the wafer including the first-generation seed does not break. The wafer including the first-generation seed crystal can be used as a seed for the next ammonothermal growth.Type: GrantFiled: March 15, 2013Date of Patent: December 1, 2015Assignees: SixPoint Materials, Inc., Seoul Semiconductor Co., Ltd.Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Patent number: 8921231Abstract: The present invention discloses a group III nitride wafer such as GaN, AlN, InN and their alloys having one surface visually distinguishable from the other surface. After slicing of the wafer from a bulk crystal of group III nitride with a mechanical method such as multiple wire saw, the wafer is chemically etched so that one surface of the wafer is visually distinguishable from the other surface. The present invention also discloses a method of producing such wafers.Type: GrantFiled: March 15, 2013Date of Patent: December 30, 2014Assignees: SixPoint Materials, Inc., Seoul Semiconductor Co., Ltd.Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Publication number: 20140087209Abstract: The present invention provides a method of growing an ingot of group III nitride. Group III nitride crystals such as GaN are grown by the ammonothermal method on both sides of a seed to form an ingot and the ingot is sliced into wafers. The wafer including the first-generation seed is sliced thicker than the other wafers so that the wafer including the first-generation seed does not break. The wafer including the first-generation seed crystal can be used as a seed for the next ammonothermal growth.Type: ApplicationFiled: March 15, 2013Publication date: March 27, 2014Applicants: Seoul Semiconductor Co., Ltd., SixPoint Materials, Inc.Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Publication number: 20140087113Abstract: The present invention provides a method of growing an ingot of group III nitride. Group III nitride crystals such as GaN are grown by the ammonothermal method on both sides of a seed to form an ingot and the ingot is sliced into wafers. The wafer including the first-generation seed is sliced thicker than the other wafers so that the wafer including the first-generation seed does not break. The wafer including the first-generation seed crystal can be used as a seed for the next ammonothermal growth.Type: ApplicationFiled: March 15, 2013Publication date: March 27, 2014Applicants: Seoul Semiconductor Co., Ltd., SixPoint Materials, Inc.Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Publication number: 20140061662Abstract: The present invention discloses a group III nitride wafer such as GaN, AlN, InN and their alloys having one surface visually distinguishable from the other surface. After slicing of the wafer from a bulk crystal of group III nitride with a mechanical method such as multiple wire saw, the wafer is chemically etched so that one surface of the wafer is visually distinguishable from the other surface. The present invention also discloses a method of producing such wafers.Type: ApplicationFiled: March 15, 2013Publication date: March 6, 2014Applicants: Seoul Semiconductor Co., Ltd., SixPoint Materials, Inc.Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Publication number: 20140065796Abstract: The present invention discloses a group III nitride wafer such as GaN, AlN, InN and their alloys having one surface visually distinguishable from the other surface. After slicing of the wafer from a bulk crystal of group III nitride with a mechanical method such as multiple wire saw, the wafer is chemically etched so that one surface of the wafer is visually distinguishable from the other surface. The present invention also discloses a method of producing such wafers.Type: ApplicationFiled: March 15, 2013Publication date: March 6, 2014Applicants: Seoul Semiconductor Co., Ltd., SixPoint Materials, Inc.Inventors: Tadao Hashimoto, Edward Letts, Sierra Hoff
-
Publication number: 20140054589Abstract: The present invention discloses a semi-insulating wafer of GaxAlyIn1-x-yN (0?x?1, 0?x+y?1) which is doped with bismuth (Bi). The semi-insulating wafer has the resistivity of 104 ohm-cm or more. Although it is very difficult to obtain a single crystal ingot of group III nitride, the ammonothermal method can grow highly-oriented poly or single crystal ingot of group III nitride having the density of dislocations/grain boundaries less than 105 cm?2. The invention also disclose the method of fabricating the semi-insulating group III nitride bulk crystals and wafers.Type: ApplicationFiled: February 28, 2013Publication date: February 27, 2014Applicants: Seoul Semiconductor Co., Ltd., SixPoint Materials, Inc.Inventors: Tadao HASHIMOTO, Edward LETTS, Sierra HOFF