# US 10,319,648 B2 · Conditions for burn-in of high power semiconductors > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,319,648 B2 - Document ID: US10319648B2 - Status: Granted - Kind: B2 - Application number: 15/955,515 - Filed: 2018-04-17 - Published: 2018-10-18 - Granted: 2019-06-11 - Earliest claimed: 2017-04-17 - Assignees: Transphorm Inc. - Applicants: Transphorm Inc. - Inventors: Kurt Vernon Smith; Likun Shen; David Michael Rhodes; Ronald Avrom Barr; James Leroy McKay - Web page: https://patentgrep.com/patent/US10319648B2 ## CPC - H10P 74/23: {characterised by multiple measurements, corrections, marking or sorting processes} - G01R 31/2621: {for testing field effect transistors, i.e. FET's} - G01R 31/2642: {Testing semiconductor operation lifetime or reliability, e.g. by accelerated life tests} - H10D 30/4755: {having wide bandgap charge-carrier supplying layers, e.g. modulation doped HEMTs such as n-AlGaAs/GaAs HEMTs} - H10D 62/8503: {Nitride Group III-V materials, e.g. AlN or GaN} - H10P 54/00: Cutting or separating of wafers, substrates or parts of devices - H10P 72/0611: {Sorting devices} - H10W 70/099: {Connecting interconnections to insulating or insulated package substrates, interposers or redistribution layers} - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract Techniques for improving reliability of III-N devices include holding the III-N devices at a first temperature less than or equal to 30° for a first period of time while applying a first gate-source voltage lower than a threshold voltage of the III-N devices and a first drain-source voltage greater than 0.2 times a break down voltage of the III-N devices; and holding the III-N devices at a second temperature greater than the first temperature for a second period of time while applying a second gate-source voltage lower than a threshold voltage of the III-N devices and a second drain-source voltage greater than 0.2 times a breakdown voltage of the III-N devices. After holding the III-N devices at the first and second temperatures, screening the III-N devices based on electrical performance of one or more parameters of the III-N devices. ## Claims ### Claim 1 A method of testing a plurality of III-N devices each comprising a source, a gate, and a drain, the method comprising: for each device, holding the device at a first temperature less than or equal to 30° C. for a first period of time while applying a first gate-source voltage lower than a threshold voltage of the device and a first drain-source voltage greater than 0.2 times a breakdown voltage of the device; for each device, holding the device at a second temperature greater than the first temperature for a second period of time while applying a second gate-source voltage lower than the threshold voltage of the device and a second drain-source voltage greater than 0.2 times the breakdown voltage of the device; after holding the devices at the first and second temperatures, testing electrical performance of one or more parameters of each of the devices; and based on results obtained from the testing, rejecting at least one device of the plurality of devices. ### Claim 2 (depends on 1) The method of claim 1, wherein the first period of time or the second period of time is greater than 24 hours. ### Claim 3 (depends on 1) The method of claim 1, wherein the second temperature is greater than 50° C. ### Claim 4 (depends on 1) The method of claim 1, wherein each of the devices is rated for operation at a minimum operating temperature, and the first temperature is less than or equal to the minimum operating temperature. ### Claim 5 (depends on 1) The method of claim 1, wherein the second temperature is greater than or equal to a median operating temperature range. ### Claim 6 (depends on 1) The method of claim 1, wherein one of the electrical performance-tested parameters is a dynamic on-resistance; and a device is rejected if the dynamic on-resistance is within 10% or greater of a maximum specified dynamic on-resistance. ### Claim 7 (depends on 1) The method of claim 1, wherein one of the electrical performance-tested parameters is an on-resistance; and a device is rejected if an increase of the on-resistance is 25% or greater compared to a previous test of the device on-resistance. ### Claim 8 (depends on 1) The method of claim 1, wherein one of the electrical performance-tested parameters is an off-state drain-source leakage; and a device is rejected if the off-state drain-source leakage is within 10% or greater of a maximum specified off-state drain-source leakage. ### Claim 9 (depends on 1) The method of claim 1, wherein one of the electrical performance-tested parameters is an off-state drain-source leakage; and a device is rejected if the off-state drain-source leakage is greater than 1 μA. ### Claim 10 (depends on 1) The method of claim 1, further comprising holding the device at one or more additional temperatures for corresponding periods of time while the drain-source voltage is greater than 0.2 times the breakdown voltage of the device, wherein the one or more additional temperatures are different from the first temperature and the second temperature. ### Claim 11 (depends on 2) The method of claim 2, further comprising packaging the plurality III-N devices into an electronic package prior to testing; wherein the packaged devices are mounted into a printed circuit board, and the printed circuit board is configured to test the plurality of III-N device simultaneously. ### Claim 12 (depends on 11) The method of claim 11, wherein the first or second drain-source voltage is greater than 400V. ### Claim 13 A method of assuring quality and reliability of a III-N device, the device including a package, a gate, a source, and a drain, the method comprising: for a first period of time, applying a first gate-source voltage below a threshold voltage of the device and applying a positive drain-source voltage; holding the package at a first temperature which is below a median operating temperature range of the device for the first period of time; and after holding the devices at the first temperature, testing electrical performance of one or more parameters of the device; and based on results obtained from the testing, rejecting the device if the performance is not within an acceptable range of one or more of the electrical performance-tested parameters. ### Claim 14 (depends on 13) The method of claim 13, further comprising, holding the device at a second temperature which is greater than a median operating temperature range of the device for a second period of time; and after holding the device at the second temperature, testing again the electrical performance of one or more parameters of the device; and based on the results obtained from the testing again, rejecting the device if the performance is not within an acceptable range of one or more of the electrical performance-tested parameters. ### Claim 15 (depends on 14) The method of claim 14, wherein the first period of time is greater than 24 hrs. ### Claim 16 (depends on 15) The method of claim 15, wherein the first period of time is less than 96 hours. ### Claim 17 (depends on 14) The method of claim 14, wherein the positive drain-source voltage is greater than 0.2 times a breakdown voltage of the device. ### Claim 18 (depends on 14) The method of claim 14, wherein one of the electrical performance-tested parameters is an off-state drain-source leakage; and a device is rejected if the off-state drain-source leakage is greater than 1 μA. ### Claim 19 (depends on 14) The method of claim 14, wherein one of the electrical performance-tested parameters is a dynamic on-resistance; and a device is rejected if the dynamic on-resistance is within 10% or greater of a maximum specified dynamic on-resistance. ### Claim 20 (depends on 14) The method of claim 14, wherein the first temperature is below 50° C. ### Claim 21 (depends on 20) The method of claim 20, wherein the second temperature is greater than 50° C. ### Claim 22 A method of testing a wafer including a plurality of III-N electronic devices each comprising a source, a gate, and a drain, the method comprising: holding the wafer at a first temperature less than or equal to 30° C. for a first period of time while simultaneously applying to a plurality of the devices a first gate-source voltage lower than a threshold voltage of the device and a first drain-source voltage greater than 0.2 times a breakdown voltage of the device; holding the wafer at a second temperature greater than the first temperature for a second period of time while simultaneously applying to a plurality of the devices a second gate-source voltage lower than the threshold voltage of the device and a second drain-source voltage greater than 0.2 times the breakdown voltage of the device; after holding the wafer at the first and second temperatures, testing electrical performance of one or more parameters of each of the devices; and based on results obtained from the testing, rejecting at least one device on the wafer. ### Claim 23 (depends on 22) The method of claim 22, wherein the first and second periods of time are each greater than 1 hour. ### Claim 24 (depends on 23) The method of claim 23, wherein a testing apparatus has a thermally controlled hot plate, and the wafer is on the hot plate; wherein during the first period of time, the hot plate is turned off; and during the second period of time, the hot plate controls a wafer temperature. ### Claim 25 (depends on 24) The method of claim 24, wherein during the second period of time, the hot plate controls the wafer temperature to greater than 50° C. ### Claim 26 (depends on 22) The method of claim 22, wherein the rejected devices are inked on the wafer and the non-inked devices are assembled into a discrete electronic package. ### Claim 27 (depends on 22) The method of claim 22, wherein one of the electrical performance-tested parameters is a dynamic on-resistance; and a device is rejected if the dynamic on-resistance is within 10% or greater of a maximum specified dynamic on resistance. ### Claim 28 (depends on 22) The method of claim 22, wherein one of the electrical performance-tested parameters is an off-state drain-source leakage: and a device is rejected if the off-state drain-source leakage is within 10% or greater of a maximum specified off-state drain-source leakage. ### Claim 29 (depends on 22) The method of claim 22, wherein one of the electrical performance-tested parameters is an on-resistance; and a device is rejected if an increase of the on-resistance is 25% or greater compared to a previous test of the device on-resistance. ### Claim 30 (depends on 22) The method of claim 22, wherein one of the electrical performance-tested parameters is an off-state drain-source leakage; and a device is rejected if the off-state drain-source leakage is greater than 1 μA. ### Claim 31 A system for testing a plurality of III-N devices, the system comprising: a testing chamber and a temperature controller; wherein the temperature controller is configured to hold the plurality of devices at a first temperature less than or equal to 30° C. for a first period of time; and during the first period of time, the testing chamber is configured to apply a first gate-source voltage lower than a threshold voltage of the device and a first drain-source voltage greater than 0.2 times a breakdown voltage of the device; and the temperature controller is configured to hold the plurality of devices at a second temperature greater than or equal to 30° C. for a second period of time; and the during the second period of time, the testing chamber is configured to apply a second gate-source voltage lower than the threshold voltage of the device and a second drain-source voltage greater than 0.2 times the breakdown voltage of the device; wherein the first period of time and the second period of time is greater than 1 hour. ### Claim 32 A method of testing a plurality of III-N devices each comprising a source, a gate, and a drain, the method comprising: for each device, holding the device at a first temperature for a first period of time while applying a first gate-source voltage lower than a threshold voltage of the device and a first drain-source voltage greater than 0.2 times a breakdown voltage of the device; for each device, holding the device at a second temperature for a second period of time while applying a second gate-source voltage lower than the threshold voltage of the device and a second drain-source voltage greater than 0.2 times the breakdown voltage of the device, wherein the second temperature is smaller than the first temperature and smaller than 30° C.; after holding the devices at the first and second temperatures, testing electrical performance of one or more parameters of each of the devices; and based on results obtained from the testing, rejecting at least one device of the plurality of devices. ### Claim 33 (depends on 32) The method of claim 32, wherein the first temperature is greater than 50° C. ### Claim 34 (depends on 32) The method of claim 32, wherein each of the devices is rated for operation at a minimum operating temperature, and the second temperature is smaller than or equal to the minimum operating temperature. ### Claim 35 (depends on 32) The method of claim 32, wherein the first temperature is greater than or equal to a median operating temperature range.