US20190363033A1 - Igbt heat dissipation structure - Google Patents
Igbt heat dissipation structure Download PDFInfo
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- US20190363033A1 US20190363033A1 US16/182,535 US201816182535A US2019363033A1 US 20190363033 A1 US20190363033 A1 US 20190363033A1 US 201816182535 A US201816182535 A US 201816182535A US 2019363033 A1 US2019363033 A1 US 2019363033A1
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- Prior art keywords
- layer
- heat dissipation
- igbt
- spray layer
- dissipation structure
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L23/00—Details of semiconductor or other solid state devices
- H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
- H01L23/36—Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks
- H01L23/373—Cooling facilitated by selection of materials for the device or materials for thermal expansion adaptation, e.g. carbon
- H01L23/3735—Laminates or multilayers, e.g. direct bond copper ceramic substrates
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- H10W40/255—
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- H10W72/073—
-
- H01L29/7393—
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10D12/00—Bipolar devices controlled by the field effect, e.g. insulated-gate bipolar transistors [IGBT]
- H10D12/411—Insulated-gate bipolar transistors [IGBT]
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10D—INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- H10D12/00—Bipolar devices controlled by the field effect, e.g. insulated-gate bipolar transistors [IGBT]
- H10D12/411—Insulated-gate bipolar transistors [IGBT]
- H10D12/441—Vertical IGBTs
-
- H10W72/07331—
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- H10W72/352—
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- H10W90/734—
Definitions
- the present disclosure relates to an IGBT (Insulated Gate Bipolar Transistor) heat dissipation structure, and in particular, to an IGBT heat dissipation structure used in electric vehicles/hybrid vehicles.
- IGBT Insulated Gate Bipolar Transistor
- IGBT Insulated Gate Bipolar Transistor
- the direct bonded copper (DBC) substrate has become the material of choice for IGBT heat dissipation structures.
- the existing IGBT heat dissipation structure mainly includes a layer 11 A of IGBT chips, an upper solder layer 12 A, a DBC substrate 13 A, a lower solder layer 14 A, and a heat dissipation layer 15 A.
- the composition of the DBC substrate 13 A is an upper metal layer 131 A, a ceramic layer 132 A, and a lower metal layer 133 A from top to bottom.
- the DBC substrate 13 A has a limited ability to spread heat. When heat is generated by the layer 11 A of IGBT chips, it cannot be transferred to the heat dissipation layer 15 A through the DBC substrate 13 A in time. Moreover, the connection between the DBC substrate 13 A and the heat dissipation layer 15 A can only be made through the lower solder layer 14 A. In practice, the entire lower solder layer 14 A is highly prone to experience an empty soldering phenomenon which causes an increase in interface impedance, thereby affecting thermal conductivity.
- One objective of the present disclosure is to provide an IGBT heat dissipation structure that can overcome the aforementioned drawbacks.
- one of the embodiments of the instant disclosure provides an IGBT heat dissipation structure, including a layer of IGBT chips, a bonding layer, a cold spray layer, a thermal spray layer, and a heat dissipation layer.
- the thermal spray layer is disposed on the heat dissipation layer.
- the cold spray layer is disposed on the thermal spray layer.
- the bonding layer is disposed on the cold spray layer, and the layer of IGBT chips is disposed on the bonding layer.
- the thermal spray layer is composed of a ceramic material.
- the ceramic material is selected from aluminum oxide, aluminum nitride or silicon nitride.
- the thermal spray layer has a thickness of about 20-500 ⁇ m.
- the cold spray layer is composed of a metal material.
- the metal material is selected from copper, copper alloy or nickel alloy.
- the cold spray layer has a thickness of about 10-1000 ⁇ m.
- the cold spray layer is further formed as a patterned layer.
- FIG. 1 is an exploded side schematic view illustrating an existing IGBT heat dissipation structure.
- FIG. 2 is a side schematic view illustrating the existing IGBT heat dissipation structure.
- FIG. 3 is an exploded side schematic view illustrating an IGBT heat dissipation structure of the present disclosure
- FIG. 4 is a side schematic view illustrating the IGBT heat dissipation structure of the present disclosure
- FIG. 5 is an enlarged schematic view of region V in FIG. 4 ;
- FIG. 6 is an enlarged schematic view of region VI in FIG. 4 .
- the IGBT heat dissipation structure in accordance with the present disclosure has a layer 11 of IGBT chips 111 , a bonding layer 12 , a cold spray layer 13 , a thermal spray layer 14 , and a heat dissipation layer 15 from top to bottom.
- the thermal spray layer 14 is disposed on top of the heat dissipation layer 15 .
- the heat dissipation layer 15 can be a heat sink or a heat dissipation metal plate.
- the thermal spray layer 14 is composed of a ceramic material.
- the thermal spray layer 14 is formed by utilizing the plasma spraying process, which raises the ceramic powder from a normal temperature to a high temperature of 2500 degrees Celsius or higher by the high heat generated by a plasma torch, thereby causing the ceramic powder to be converted from a solid state to a molten liquid state.
- the molten ceramic is then blown by a high-velocity plasma gas, atomized, and sprayed on the surface of the heat dissipation layer 15 to form a thermal spray layer having a predetermined thickness.
- the plasma gas used in the present embodiment is argon; however, nitrogen, hydrogen, and other gases may also be used. Therefore, compared with the existing method of using a solder layer to form a connection between the DBC substrate and the heat dissipation layer, the IGBT heat dissipation structure in accordance with the present disclosure forms the thermal spray layer 14 directly on the surface of the heat dissipation layer 15 without having to go through a solder layer.
- the ceramic material of the thermal spray layer 14 can be selected from aluminum oxide, but it can also be selected from aluminum nitride or silicon nitride.
- the thickness of the thermal spray layer 14 may be set in advance according to the spraying time of the spray coating on the surface of the heat dissipation layer 15 .
- the thermal spray layer 14 has a thickness of about 20-500 ⁇ m, but preferably 400 ⁇ m, to achieve better insulation and heat conduction.
- the cold spray layer 13 is disposed on top of the thermal spray layer 14 and is composed of a metal material.
- the cold spray layer 13 is constructed by accelerating the metal powder by a supersonic gas flow, causing the metal powder to crash into the surface of the thermal spray layer 14 at a high speed to be embedded in the thermal spray layer 14 .
- the metal powder produces a large amount of plastic deformation, and the original powder morphology is no longer maintained.
- the metal powder after a large amount of plastic deformation is stacked into a dense layered structure to form a cold spray layer having a predetermined thickness.
- the thickness of the cold spray layer 13 is between 10-1000 ⁇ m, preferably 300 ⁇ m.
- the metal material of the cold spray layer 13 can be selected from copper, copper alloy or nickel alloy, but it can also be selected from other metals.
- the cold spray layer can be formed as a patterned layer by a masking technique on a predetermined area of the surface of the thermal spray layer 14 .
- the bonding layer 12 is disposed on top of the cold spray layer 13 , and the layer 11 of IGBT chips 111 is disposed on top of the bonding layer 12 .
- the bonding layer 12 can be a tin bonding layer, but it can also be a sintered silver layer.
- the layer 11 of IGBT chips 111 may include one or more IGBT chips 111 .
- the one or more IGBT chips 111 are bonded onto the cold spray layer 13 through the bonding layer 12 .
- the heat generated by the one or more IGBT chips 111 can be conducted to the heat dissipation layer 15 by the cold spray layer 13 and the thermal spray layer 14 to dissipate heat outward.
- the bottom surface of the thermal spray layer 14 is formed with first microstructures 141 that are completely embedded within the top surface of the heat dissipation layer 15 to enhance the bonding strength between the two surfaces that are secured together.
- the first microstructures 141 have non-uniform shapes and sizes, as shown in FIG. 5 .
- the bottom surface of the cold spray layer 13 is formed with second microstructures 131 that are completely embedded within the top surface of the thermal spray layer 14 to enhance the bonding strength between the two surfaces that are secured together.
- the second microstructures 131 have non-uniform shapes and sizes, as shown in FIG. 6 .
- the cold spray layer 13 has a cross-sectional area smaller than the thermal spray layer 14
- the thermal spray layer 14 has a cross-sectional area smaller than the heat dissipation layer 15 .
- the IGBT heat dissipation structure in accordance with the present disclosure forms a cold spray layer 13 and a thermal spray layer 14 respectively by two spray methods to rapidly and uniformly conduct the heat of the IGBT chips to the heat dissipation fins of the heat dissipation layer 15 .
- the IGBT heat dissipation structure in accordance with the present disclosure can simultaneously achieve the advantages of the electrical and thermal conductivity of the cold sprayed metal material and the higher breakdown voltage of the thermal sprayed ceramic material.
- the thermal spray layer is formed directly on the surface of the heat dissipation layer without having to go through a solder layer, so that the heat conduction performance is not affected by the problems of empty soldering and the interface impedance of the solder layer, thereby making the heat dissipation layer capable of having maximum heat absorption and heat dissipation performance.
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
Abstract
Description
- The present disclosure relates to an IGBT (Insulated Gate Bipolar Transistor) heat dissipation structure, and in particular, to an IGBT heat dissipation structure used in electric vehicles/hybrid vehicles.
- Most of the high-power inverters currently used in electric vehicles/hybrid vehicles use IGBT (Insulated Gate Bipolar Transistor) chips. Therefore, the heat generated by the high-power inverters during operation will cause the IGBT chip temperature to rise. If no proper heat dissipation measures are incorporated, the temperature of the IGBT chip may exceed the allowable temperature, resulting in deterioration of performance and damage. Therefore, the IGBT heat dissipating efficiency has become a major problem in the industry.
- At present, the direct bonded copper (DBC) substrate has become the material of choice for IGBT heat dissipation structures. Referring to
FIGS. 1 and 2 , the existing IGBT heat dissipation structure mainly includes alayer 11A of IGBT chips, anupper solder layer 12A, aDBC substrate 13A, alower solder layer 14A, and aheat dissipation layer 15A. Among them, the composition of theDBC substrate 13A is anupper metal layer 131A, aceramic layer 132A, and alower metal layer 133A from top to bottom. - However, the
DBC substrate 13A has a limited ability to spread heat. When heat is generated by thelayer 11A of IGBT chips, it cannot be transferred to theheat dissipation layer 15A through theDBC substrate 13A in time. Moreover, the connection between theDBC substrate 13A and theheat dissipation layer 15A can only be made through thelower solder layer 14A. In practice, the entirelower solder layer 14A is highly prone to experience an empty soldering phenomenon which causes an increase in interface impedance, thereby affecting thermal conductivity. - The abovementioned drawbacks of the existing IGBT heat dissipation structure suggest that there is still room for improvement in the art.
- One objective of the present disclosure is to provide an IGBT heat dissipation structure that can overcome the aforementioned drawbacks.
- In order to achieve the object above, one of the embodiments of the instant disclosure provides an IGBT heat dissipation structure, including a layer of IGBT chips, a bonding layer, a cold spray layer, a thermal spray layer, and a heat dissipation layer. The thermal spray layer is disposed on the heat dissipation layer. The cold spray layer is disposed on the thermal spray layer. The bonding layer is disposed on the cold spray layer, and the layer of IGBT chips is disposed on the bonding layer.
- Preferably, the thermal spray layer is composed of a ceramic material.
- Preferably, the ceramic material is selected from aluminum oxide, aluminum nitride or silicon nitride.
- Preferably, the thermal spray layer has a thickness of about 20-500 μm.
- Preferably, the cold spray layer is composed of a metal material.
- Preferably, the metal material is selected from copper, copper alloy or nickel alloy.
- Preferably, the cold spray layer has a thickness of about 10-1000 μm.
- Preferably, the cold spray layer is further formed as a patterned layer.
- For further understanding of the present disclosure, the following embodiments are provided to facilitate the disclosure of the present disclosure.
-
FIG. 1 is an exploded side schematic view illustrating an existing IGBT heat dissipation structure. -
FIG. 2 is a side schematic view illustrating the existing IGBT heat dissipation structure. -
FIG. 3 is an exploded side schematic view illustrating an IGBT heat dissipation structure of the present disclosure; -
FIG. 4 is a side schematic view illustrating the IGBT heat dissipation structure of the present disclosure; -
FIG. 5 is an enlarged schematic view of region V inFIG. 4 ; -
FIG. 6 is an enlarged schematic view of region VI inFIG. 4 . - The aforementioned illustrations and following detailed descriptions are exemplary for the purpose of further explaining the scope of the instant disclosure. Other objectives and advantages related to the instant disclosure will be illustrated in the subsequent descriptions and appended drawings.
- Referring to
FIGS. 3 and 4 , the IGBT heat dissipation structure in accordance with the present disclosure has alayer 11 ofIGBT chips 111, abonding layer 12, acold spray layer 13, athermal spray layer 14, and aheat dissipation layer 15 from top to bottom. - The
thermal spray layer 14 is disposed on top of theheat dissipation layer 15. Theheat dissipation layer 15 can be a heat sink or a heat dissipation metal plate. Thethermal spray layer 14 is composed of a ceramic material. - In detail, the
thermal spray layer 14 is formed by utilizing the plasma spraying process, which raises the ceramic powder from a normal temperature to a high temperature of 2500 degrees Celsius or higher by the high heat generated by a plasma torch, thereby causing the ceramic powder to be converted from a solid state to a molten liquid state. The molten ceramic is then blown by a high-velocity plasma gas, atomized, and sprayed on the surface of theheat dissipation layer 15 to form a thermal spray layer having a predetermined thickness. - The plasma gas used in the present embodiment is argon; however, nitrogen, hydrogen, and other gases may also be used. Therefore, compared with the existing method of using a solder layer to form a connection between the DBC substrate and the heat dissipation layer, the IGBT heat dissipation structure in accordance with the present disclosure forms the
thermal spray layer 14 directly on the surface of theheat dissipation layer 15 without having to go through a solder layer. - Furthermore, the ceramic material of the
thermal spray layer 14 can be selected from aluminum oxide, but it can also be selected from aluminum nitride or silicon nitride. In addition, the thickness of thethermal spray layer 14 may be set in advance according to the spraying time of the spray coating on the surface of theheat dissipation layer 15. In the present embodiment, thethermal spray layer 14 has a thickness of about 20-500 μm, but preferably 400 μm, to achieve better insulation and heat conduction. - The
cold spray layer 13 is disposed on top of thethermal spray layer 14 and is composed of a metal material. - In detail, the
cold spray layer 13 is constructed by accelerating the metal powder by a supersonic gas flow, causing the metal powder to crash into the surface of thethermal spray layer 14 at a high speed to be embedded in thethermal spray layer 14. At the same time, the metal powder produces a large amount of plastic deformation, and the original powder morphology is no longer maintained. The metal powder after a large amount of plastic deformation is stacked into a dense layered structure to form a cold spray layer having a predetermined thickness. - In the present embodiment, the thickness of the
cold spray layer 13 is between 10-1000 μm, preferably 300 μm. - Furthermore, the metal material of the
cold spray layer 13 can be selected from copper, copper alloy or nickel alloy, but it can also be selected from other metals. In addition, the cold spray layer can be formed as a patterned layer by a masking technique on a predetermined area of the surface of thethermal spray layer 14. - The
bonding layer 12 is disposed on top of thecold spray layer 13, and thelayer 11 ofIGBT chips 111 is disposed on top of thebonding layer 12. Thebonding layer 12 can be a tin bonding layer, but it can also be a sintered silver layer. - The
layer 11 ofIGBT chips 111 may include one ormore IGBT chips 111. In addition, the one ormore IGBT chips 111 are bonded onto thecold spray layer 13 through thebonding layer 12. The heat generated by the one ormore IGBT chips 111 can be conducted to theheat dissipation layer 15 by thecold spray layer 13 and thethermal spray layer 14 to dissipate heat outward. - It is worth mentioning that, the bottom surface of the
thermal spray layer 14 is formed withfirst microstructures 141 that are completely embedded within the top surface of theheat dissipation layer 15 to enhance the bonding strength between the two surfaces that are secured together. Thefirst microstructures 141 have non-uniform shapes and sizes, as shown inFIG. 5 . Similarly, the bottom surface of thecold spray layer 13 is formed withsecond microstructures 131 that are completely embedded within the top surface of thethermal spray layer 14 to enhance the bonding strength between the two surfaces that are secured together. Thesecond microstructures 131 have non-uniform shapes and sizes, as shown inFIG. 6 . Furthermore, thecold spray layer 13 has a cross-sectional area smaller than thethermal spray layer 14, and thethermal spray layer 14 has a cross-sectional area smaller than theheat dissipation layer 15. - In summary, the IGBT heat dissipation structure in accordance with the present disclosure forms a
cold spray layer 13 and athermal spray layer 14 respectively by two spray methods to rapidly and uniformly conduct the heat of the IGBT chips to the heat dissipation fins of theheat dissipation layer 15. Compared with the DBC substrate of the existing IGBT heat dissipation structure, the IGBT heat dissipation structure in accordance with the present disclosure can simultaneously achieve the advantages of the electrical and thermal conductivity of the cold sprayed metal material and the higher breakdown voltage of the thermal sprayed ceramic material. Moreover, the thermal spray layer is formed directly on the surface of the heat dissipation layer without having to go through a solder layer, so that the heat conduction performance is not affected by the problems of empty soldering and the interface impedance of the solder layer, thereby making the heat dissipation layer capable of having maximum heat absorption and heat dissipation performance.
Claims (10)
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| TW107118138 | 2018-05-28 | ||
| TW107118138A | 2018-05-28 | ||
| TW107118138A TW202005020A (en) | 2018-05-28 | 2018-05-28 | IGBT module with heat dissipation structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| US10475723B1 US10475723B1 (en) | 2019-11-12 |
| US20190363033A1 true US20190363033A1 (en) | 2019-11-28 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US16/182,535 Active US10475723B1 (en) | 2018-05-28 | 2018-11-06 | IGBT heat dissipation structure |
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| US (1) | US10475723B1 (en) |
| TW (1) | TW202005020A (en) |
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| US9335296B2 (en) | 2012-10-10 | 2016-05-10 | Westinghouse Electric Company Llc | Systems and methods for steam generator tube analysis for detection of tube degradation |
| US11935662B2 (en) | 2019-07-02 | 2024-03-19 | Westinghouse Electric Company Llc | Elongate SiC fuel elements |
| WO2021055284A1 (en) | 2019-09-19 | 2021-03-25 | Westinghouse Electric Company Llc | Apparatus for performing in-situ adhesion test of cold spray deposits and method of employing |
| CN114150311A (en) * | 2020-08-17 | 2022-03-08 | 中国科学院金属研究所 | A kind of ceramic/copper composite substrate and preparation method thereof |
| TWI759199B (en) * | 2021-05-07 | 2022-03-21 | 艾姆勒車電股份有限公司 | Thermal conductive substrate structure with a non-rectangular heat-dissipation layer |
| KR102866116B1 (en) | 2021-11-26 | 2025-09-30 | 삼성전자주식회사 | Semiconductor package |
| CN114737182A (en) * | 2022-05-07 | 2022-07-12 | 无锡市新达共创纳米科技有限公司 | Preparation method of Hastelloy coating of conductive roller of copper foil post-processor |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US8018056B2 (en) * | 2005-12-21 | 2011-09-13 | International Rectifier Corporation | Package for high power density devices |
| US7508012B2 (en) * | 2006-01-18 | 2009-03-24 | Infineon Technologies Ag | Electronic component and method for its assembly |
| JP2007288054A (en) * | 2006-04-19 | 2007-11-01 | Toyota Motor Corp | Power module |
| JP5664625B2 (en) * | 2012-10-09 | 2015-02-04 | 三菱マテリアル株式会社 | Semiconductor device, ceramic circuit board, and semiconductor device manufacturing method |
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2018
- 2018-05-28 TW TW107118138A patent/TW202005020A/en unknown
- 2018-11-06 US US16/182,535 patent/US10475723B1/en active Active
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| Publication number | Publication date |
|---|---|
| US10475723B1 (en) | 2019-11-12 |
| TW202005020A (en) | 2020-01-16 |
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