TC 47 - Semiconductor devices

IEC 60749-21:2025 establishes a standard procedure for determining the solderability of device package terminations that are intended to be joined to another surface using tin-lead (SnPb) or lead-free (Pb-free) solder for the attachment. This test method provides a procedure for “dip and look” solderability testing of through hole, axial and surface mount devices (SMDs) as well as an optional procedure for a board mounting solderability test for SMDs for the purpose of allowing simulation of the soldering process to be used in the device application. The test method also provides optional conditions for ageing. This test is considered destructive unless otherwise detailed in the relevant specification.
NOTE 1 This test method does not assess the effect of thermal stresses which can occur during the soldering process. More details can be found in IEC 60749‑15 or IEC 60749‑20.
NOTE 2 If a qualitative test method is preferred, the Wetting balance test method can be found in IEC 60068-2-69.
This edition includes the following significant technical changes with respect to the previous edition:
- revision to certain operating conditions in line with current working practices.

IEC 60749-23:2025 specifies the test used to determine the effects of bias conditions and temperature on solid state devices over time. It simulates the device operating condition in an accelerated way and is primarily for device qualification and reliability monitoring. A form of high temperature bias life using a short duration, popularly known as "burn-in", can be used to screen for infant-mortality related failures. The detailed use and application of burn-in is outside the scope of this document.
This edition includes the following significant technical changes with respect to the previous edition:
a) absolute stress test definitions and resultant test durations have been updated.

IEC 60749-24:2025 specifies unbiased highly accelerated stress testing (HAST). HAST is performed for the purpose of evaluating the reliability of non-hermetically packaged solid-state devices in humid environments. It is a highly accelerated test which employs temperature and humidity under non-condensing conditions to accelerate the penetration of moisture through the external protective material (encapsulant or seal) or along the interface between the external protective material and the metallic conductors which pass through it. Bias is not applied in this test to ensure that the failure mechanisms potentially overshadowed by bias can be uncovered (e.g. galvanic corrosion).
This test is used to identify failure mechanisms internal to the package and is destructive.
This edition includes the following significant technical changes with respect to the previous edition:
a) rearrangement of clauses to reposition requirements;
b) addition of two notes to the post-test electrical procedures.

IEC 60749-7:2025 specifies the testing and measurement of water vapour and other gas content of the atmosphere inside a metal or ceramic hermetically sealed device. The test is used as a measure of the quality of the sealing process and to provide information about the long-term chemical stability of the atmosphere inside the package. It is applicable to semiconductor devices sealed in such a manner but generally only used for high reliability applications such as military or aerospace.
Of particular interest is the measurement of the primary sealing gases (or lack thereof), the moisture content, the presence of bombing gases that are indicative of non-hermeticity (e.g. helium), oxygen to argon ratio indicative of room air ~ 20 to 1 (± 10 %), dissimilar concentration of internally sealed gases (e.g. nitrogen, helium) than originally sealed in the device package, the presence of leak test fluid (i.e. fluorocarbon, helium, air), and all other gases to determine if the device meets the specified moisture, hermeticity and other criteria. Also of interest is the measurement of all the other gases since they reflect upon the quality of the sealing process and provide information about the long-term chemical stability of the atmosphere inside the device. The presence of leak test fluorocarbon vapour in the internal gas analysis (IGA) is an indication of failure to meet leak test requirements of IEC 60749‑8.
This test is destructive.
This edition includes the following significant technical changes with respect to the previous edition:
a) This document has been re-written and rearranged to align with the text of MIL-STD-883, Method 1018.10.
b) Additional detail has been provided in the calibration requirements.

IEC 60749-22-1:2025 provides a means for determining the strength and failure mode of a wire bonded to, and the corresponding interconnects on, a die or package bonding surface and can be performed on unencapsulated or decapsulated devices. This test method can be performed on gold alloy, copper alloy, and silver alloy thermosonic (ball and stitch) bonds made of wire ranging in diameter from 15 µm to 76 µm (0,000 6" to 0,003"); and on gold alloy, copper alloy, and aluminium alloy ultrasonic (wedge) bonds made of wire ranging in diameter from 18 µm to 600 µm (0,000 7" to 0,024").
This wire bond pull test method is destructive. It is appropriate for use in process development, process control, or quality assurance.
This test method allows for two distinct methods of pulling wires:
a) One method incorporates the use of a hook that is placed under the wire and is then pulled.
b) One method requires that after the wire be cut, a clamp is placed on the wire connected to the bond to be tested, and this clamp is used to pull the wire.
This test method does not include bond strength testing using wire bond shear testing. Wire bond shear testing is described in IEC 60749-22-2.
This first edition, together with the first edition of IEC 60749-22-2:2025, cancels and replaces the first edition of IEC 60749-22 published in 2002.
This edition includes the following significant technical changes with respect to the previous edition:
a) Major update, including new techniques and use of new materials (e.g. copper wire) involving a complete rewrite as two separate subparts (this document and IEC 60749-22-2).
This International Standard is to be used in conjunction with IEC 60749-22-2:2025.

IEC 60749-22-2:2025 establishes a means for determining the strength of a ball bond to a die or package bonding surface and can be performed on pre-encapsulation or post-encapsulation devices. This measure of bond strength is extremely important in determining two features:
a) the integrity of the metallurgical bond which has been formed, and
b) the quality of ball bonds to die or package bonding surfaces.
This test method covers thermosonic (ball) bonds made with small diameter wire from 15 µm to 76 µm (0,000 6" to 0,003").
This test method can only be used when the bonds are large enough to allow for proper contact with the shear test chisel and when there are no adjacent interfering structures that would hinder the movement of the chisel. For consistent shear results the ball height will be at least 4,0 µm (0,000 6 ") for ball bonds, which is the current state of the art for bond shear test equipment at the time of this revision.
This test method can also be used on ball bonds that have had their wire removed and on to which a second bond wire (typically a stitch bond) is placed. This is known as "stitch on ball" and "reverse bonding". See Annex A for additional information.
The wire bond shear test is destructive. It is appropriate for use in process development, process control, or quality assurance, or both.
This test method can be used on ultrasonic (wedge) bonds, however its use has not been shown to be a consistent indicator of bond integrity. See Annex B for information on performing shear testing on wedge bonds.
This test method does not include bond strength testing using wire bond pull testing. Wire bond pull testing is described in IEC 60749-22-1.
This first edition, together with the first edition of IEC 60749-22-1, cancels and replaces the first edition IEC 60749-22 published in 2002. This International Standard is to be used in conjunction with IEC 60749-22-1:2025.
This edition includes the following significant technical changes with respect to the previous edition:
a) Major update, including new techniques and use of new materials (e.g. copper wire) involving a complete rewrite as two separate subparts (this document and IEC 60749‑22‑1).

IEC 62047-49:2025 specifies reliability test methods of electro-mechanical conversion characteristics of piezoelectric thin film on microcantilever, which is typical structure of micro sensors and micro actuators. In order to estimate the stability of the piezoelectric coefficient of the piezoelectric thin films with microscale structures in the operating conditions, this document reports the schema to determine the characteristic parameters for consumer, industry or any other applications of piezoelectric MEMS devices. This document applies to piezoelectric thin films on microcantilever fabricated by MEMS process.

IEC 63150-3:2025 specifies terms and definitions, and test methods of impact-driven energy harvesting devices of which electric energy is generated by impact force of human walking or running motion under practical human motion. This document is applicable to impact-driven energy harvesting devices embedded in wearables, especially, shoe-mounted energy harvesters, whose main element of the power generation is the impact energy. This measuring method is independent of power generation principles (such as piezoelectric, electrostatic, triboelectric, electromagnetic, etc.). According to typical human motion, power generation performance is measured in the condition of large-amplitude and low-frequency external mechanical excitation.

IEC 63150-2:2025 specifies terms and definitions, and test methods that can be used to evaluate and determine the performance characteristics of kinetic energy harvesting devices for human arm swing motion. Such kinetic energy harvesting devices often have a rotor with eccentric mass to efficiently capture kinetic energy at very low frequency range, but this document is not limited to rotational energy harvesters. These have different power generation mechanisms (such as electromagnetic, piezoelectric, electrostatic, triboelectric, etc.) with different working principles, and their performance is evaluated with motions relevant to human arm swing, in which large-amplitude low-frequency external mechanical excitations prevail.

IEC 62047-53:2025 defines the test methods for the performances of MEMS electrothermal transfer device.
The document is applicable to the MEMS electrothermal transfer devices used in airbags, petroleum and mineral detection, igniters and detonators.

IEC 60747-6:2025 specifies product specific standards for terminology, letter symbols, essential ratings and characteristics (properties), measuring and test methods, requirements for type tests, routine tests, endurance tests and marking for the following discrete semiconductor devices:
- reverse blocking triode thyristors;
- reverse conducting (triode) thyristors;
- bidirectional triode thyristors (triacs);
- turn-off thyristors.
If no ambiguity is likely to result, any of the above will be referred to as thyristors.
This edition includes the following significant technical changes with respect to the previous edition:
a) the terms and definitions for partial thermal resistance junction-to-case and voltages related to ratings and characteristics (properties) have been added;
b) Clauses 3, 4, 5, 6 and 7 were amended with some deletions of information no longer in use and with some necessary additions.

IEC 60747-2:2025 specifies product specific standards for terminology, letter symbols, essential ratings and characteristics (properties), measuring and test methods, requirements for type tests, routine tests, endurance tests and marking for the following discrete semiconductor devices:
- generic rectifier diodes;
- avalanche rectifier diodes;
- fast-switching rectifier diodes;
- Schottky barrier diodes.
If no ambiguity is likely to result, any of the above will be referred to as diodes.
This edition includes the following significant technical changes with respect to the previous edition:
a) the terms and definitions for partial thermal resistance junction-to-case have been added;
b) Clauses 3, 4, 5, 6 and 7 have been amended with some deletions of information no longer in use and with some necessary additions.

IEC TR 62433-4-1:2025 provides an overview of good practices to extract an ICIM-CI model from measurements and to build a numerical model of the PCB in which the ICIM-CI model is used to predict RF immunity of an IC in its application PCB.
This document also discusses factors which can be considered to obtain proper results in an ICIM-CI model extraction and use of the actual model at the PCB level.

IEC 60749-34-1:2025 describes a test method that is used to determine the capability of power semiconductor modules to withstand thermal and mechanical stress resulting from cycling the power dissipation of the internal semiconductors and the internal connectors. It is based on IEC 60749-34, but is developed specifically for power semiconductor module products, including insulated-gate bipolar transistor (IGBT), metal-oxide-semiconductor field-effect transistor (MOSFET), diode and thyristor.
If there is a customer request for an individual use or an application specific guideline (for example ECPE Guideline AQG 324), details of the test method can be based on these requirements if they deviate from the content of this document.
This test caused wear-out and is considered destructive.

IEC TR 63571:2025 describes a method to calculate “SYSTEM”-level lifetime from “PART”-level lifetime. It presents a general mathematical theory and simple calculation examples for educational purposes. Of the elements related to “SYSTEM”-level lifetime, software-related elements such as diagnostics are outside the scope of this document.

IEC 63378-3:2025 specifies the thermal circuit network model of discrete (TO‑243, TO‑252 and TO‑263) packages, which is used in the transient analysis of electronic devices to estimate precise junction temperatures without experimental verification.
This model is intended to be made and provided by semiconductor suppliers and to be used by assembly makers of electronic devices.

IEC 62047-50:2025 defines the test conditions and test methods for the performance of MEMS capacitive microphones.
This document applies to MEMS capacitive microphones.

IEC 62047-46:2025 specifies the requirements and testing method to measure the tensile strength of membrane with nanoscale thickness (length from 100 μm to 5 000 μm, width from 100 μm to 1 000 μm, thickness from 50 nm to 500 nm) which is fabricated by micromachining technology used in silicon-based micro-electromechanical system (MEMS).
This document is applicable to in-situ tensile strength measurement of nanoscale thickness membrane manufactured by microelectronics technology and related micromachining technology.
With the devices scaling, the tensile strength degradation, induced by defects and contaminations, becomes severer. This document specifies an in-situ testing method of the tensile strength of membrane with nanoscale thickness based on a MEMS technique. This document does not need intricate instruments (such as scanning probe microscopy and nanoindenter) and special test specimens.
Since in-situ on-chip tester in this document and device are fabricated with the same process on the same wafer, this document can give some practical reference for the design part.

IEC 63505:2025 gives guidance on VT measurement methods and conditioning prior to VT testing in SiC power MOSFETs to reduce or eliminate the effect of the aforementioned hysteresis. The method is applicable for PBTI testing, NBTI and threshold voltage changes caused by switching events are excluded from the scope.
SiC MOSFETs have threshold voltage hysteresis caused by transient trap effects, which impacts the evaluation of the actual the VT shift caused by stress tests such as bias temperature instabilities (BTI).

IEC 62047-45:2025 specifies the requirements and testing method to measure the impact resistance of nanostructures which are fabricated by micromachining technology used in silicon-based micro-electromechanical system (MEMS).
This document is applicable to the in-situ impact resistance measurement of nanostructures manufactured by microelectronic technology process and other micromachining technology.
In the production of MEMS devices, due to the micro/nano size, the non-ideal effect of fabrication is greatly amplified compared with the macroscale. Surface defects, line width loss, and residual stress can occur in the fabricated object, resulting in severe fluctuations in the mechanical strength of MEMS devices. This document specifies an in-situ measurement method for the impact resistance of nanostructures based on MEMS technology to extract the impact strength of actual manufactured structures. This test method does not need intricated instruments (such as scanning probe microscopy and nanoindenter) and special test specimens.
Since the in-situ on-chip tester in this document can be implanted in device fabrication as a standard detection pattern, this document can provide a bridge, by which the fabrication part can give some quantitative reference for the design part.

IEC 60747-5-4:2022 specifies the terminology, the essential ratings and characteristics as well as the measuring methods of semiconductor lasers.
This edition includes the following significant technical changes with respect to the previous edition:
- References for the terms and definitions related to the lighting area, IEC 60050-845, are revised based on IEC 60050-845:2020;
- Emission angle is changed to radiation angle in 3.3.2;
- Definitions of rise time and fall time in 3.4.1 are revised based on the publication IEC 60050-521:2002;
- Spectral linewidth is added to Table 1 in Clause 4;
- Conditions for carrier-to-noise ratio of Table 1 in Clause 4 is amended.
- Error in the equation for carrier-to-noise ratio in 5.2.2 is corrected;
- Precaution against the equipment used for carrier-to-noise ratio measurement is added in 5.2.2;
- Explanation for the measurement method of the small signal cut-off frequency in 5.3.2 of the first edition is deleted because it has been defined in the latest version of ISO 11554;
- Reference document for the lifetime in 5.4 is amended;
- Precaution against the measuring arrangement used for the half-intensity width and 1/e2-intensity is added in 5.5.3;
- Reference tables in Annex A, Annex B and Annex C are revised by following the latest version of ISO publications.

IEC 60747-15:2024 gives the requirements for isolated power semiconductor devices. These requirements are additional to those given in other parts of IEC 60747 for the corresponding non-isolated power devices and parts of IEC 60748 for ICs. This third edition includes the following significant technical changes with respect to the previous edition:
a) The intelligent power semiconductor modules (IPM), which was previously excluded from the first and second edition, is now included in this document (Annex C);
b) The thermal resistance is described for each switch (6.2.4);
c) Added isolation test between temperature sensor and terminals, in case there is an agreement with the user (6.1.2).

IEC 63378-2-1:2024 specifies three-dimensional (3D) thermal models of discrete semiconductor packages (TO-243, TO-252 and TO-263), utilized in the steady-state thermal analysis of electronic devices to estimate junction temperatures accurately.
This model is assumed to be made by semiconductor suppliers and to be used by assembly makers of electronic devices.

IEC 60747-16-9:2024 specifies the terminology, essential ratings, and characteristics, and measuring methods of microwave integrated circuit phase shifters.

IEC 62047-47:2024 specifies the requirements and testing method to measure the bending strength of microstructures which are fabricated by micromachining technology used in silicon-based micro-electromechanical system (MEMS).
This document is applicable to the in-situ bending strength measurement of microstructures manufactured by microelectronic technology process and other micromachining technology.
With the devices scaling, the bending strength degradation, induced by defects and contaminations, becomes more severe. This document specifies an in-situ testing method of the bending strength based on MEMS technique. This document does not need intricate instruments (such as scanning probe microscopy and nanoindenter) and special test specimens.
Since in-situ on-chip tester in this document and device are fabricated with the same process on the same wafer, this document can give some practical reference for the design part.

IEC 62047-48:2024 specifies the requirements and testing method to determine the solution concentration by optical absorption using MEMS fluidic device.

IEC 62047-43:2024 specifies the test method of electrical characteristics after cyclic bending deformation for flexible electromechanical devices. These devices include passive micro components and active micro components on the flexible film or embedded in the flexible film. The desired in-plane dimensions of the device for the test method ranges typically from 1 mm to 300 mm and the thickness ranges from 10 μm to 1 mm, but these are not limiting values. The test method is so designed as to understand and further visualize the entire performance deterioration behaviour after cyclic bending deformation in a concept of 3D (P-S-N: Performance - Severity of bending - Number of cycles) plot over the loading space of severity of bending and number of repeated cycles. This document is essential to estimate safety margin over the operation period under a certain level of cyclic bending deformation and indispensable for reliable design of the product employing these devices.

IEC 62047-44:2024 describes terminology, definitions and test methods that are used to evaluate and determine the dynamic performance of MEMS (Micro-Electromechanical Systems) resonant electric‑field‑sensitive devices. It also specifies sample requirements and test equipment for dynamic performances of MEMS resonant electric‑field‑sensitive devices. The statements made in this document are also applicable to MEMS resonant electric‑field‑sensitive devices with various driving mechanisms such as electrostatic, electrothermal, electromagnetic, piezoelectric, etc.

IEC 60749-5:2023 provides a steady-state temperature and humidity bias life test to evaluate the reliability of non-hermetic packaged semiconductor devices in humid environments. This test method is considered destructive. This edition includes the following significant technical changes with respect to the previous edition:
a) The specification of the test equipment is changed to require the need to minimize relative humidity gradients and maximize air flow between semiconductor devices under test;
b) The specification of the test equipment fixtures is changed to require the avoidance of condensation on devices under test and on electrical fixtures connecting the devices to the test equipment;
c) replacement of references to “virtual junction” with “die”.

IEC 61967-8:2023 defines a method for measuring the electromagnetic radiated emission from an integrated circuit (IC) using an IC stripline. The IC being evaluated is mounted on an EMC test board (PCB) between the active conductor and the ground plane of the IC stripline arrangement. This edition includes the following significant technical changes with respect to the previous edition:
a) frequency range of 150 kHz to 3 GHz was deleted from the scope;
b) extension of upper usable frequency to 6 GHz or higher as long as the defined requirements are fulfilled.

IEC 63287-2:2023 gives guidelines for the development of reliability qualification plans using the concept of mission profile, based on the environmental conditioning and proposed usage of the product. This document is not intended for military- and space-related applications.

IEC 60747-5-16:2023 specifies the measuring method of flat-band voltage of single GaN-based light emitting diode (LED) die or package without phosphor, based on the photocurrent (PC) spectroscopy. White LEDs for lighting applications are out of the scope of this part of IEC 60747.

IEC 60747-18-5:2023(E) specifies the evaluation method for light responsivity characteristics of lens-free CMOS photonic array sensor package modules by incident angle of light. This document includes the test setup, test procedure, test item, and test report for lens-free CMOS photonic array sensor package modules.

IEC 60747-18-4:2023(E) specifies the evaluation method for noise characteristics of lens-free CMOS photonic array sensors. This document includes the measurement setup, test procedure, test items, evaluation method, and test report for noise characteristics of lens-free CMOS photonic array sensors.

IEC 62951-8:2023 (E) defines terms and specifies the test method for evaluating the stretchability, flexibility, and stability of flexible resistive memory. The test method descriptions include experimental procedures and the equipment to be used. It also includes general requirements for test conditions such as the temperature and relative humidity of the testing environment. The test method described in this document focuses on stability evaluation rather than reliability.

IEC 63364-1:2022 specifies terms, the test method, and the report of sound variation detection system based on IoT. It provides the evaluation method for each part of the sound variation detection system based on IoT in the block diagram, the characterization parameters, symbols, test setups and the conditions. In addition, this document defines the configuration items and criteria of standard space and firing situation for the quality evaluation measurement of sound field variation detection system with IoT.

IEC 62951-9:2022(E) specifies the test methods for evaluating the performance of unipolar-type one transistor one resistor (1T1R) resistive memory cells. The performance test methods in this document include read, forming, SET, RESET, endurance and retention. This document is applicable to flexible devices as well as rigid resistive memory devices without any limitations prone to device technology and size.

IEC 60747-16-7:2022 specifies the terminology, essential ratings and characteristics, and measuring methods of microwave integrated circuit attenuators.

IEC 60747-16-8:2022 specifies the terminology, essential ratings and characteristics, and measuring methods of microwave integrated circuit limiters.

IEC 62228-6:2022 specifies test and measurement methods for EMC evaluation of peripheral sensor interface 5 (PSI5) transceiver integrated circuits (ICs) under network condition. It defines test configurations, test conditions, test signals, failure criteria, test procedures, test setups and test boards. It is applicable for PSI5 satellite ICs (e.g. sensors) and ICs with embedded PSI5 transceivers (e.g. PSI5 electronic control unit IC). The document covers
the emission of RF disturbances,
the immunity against RF disturbances,
the immunity against impulses, and
the immunity against electrostatic discharges (ESD).

IEC 60749-37:2022 provides a test method that is intended to evaluate and compare drop performance of surface mount electronic components for handheld electronic product applications in an accelerated test environment, where excessive flexure of a circuit board causes product failure. The purpose is to standardize the test board and test methodology to provide a reproducible assessment of the drop test performance of surface-mounted components while producing the same failure modes normally observed during product level test. This edition includes the following significant technical changes with respect to the previous edition:
- correction of a previous technical error concerning test conditions;
- updates to reflect improvements in technology.

IEC TR 63357:2022(E) describes standardization roadmap of fault test methods for integrated circuits used in automotive vehicles. Since automotive vehicles are exposed in harsh environment such as very low or high temperature, vibration, high frequency signals, etc. Therefore, they are tested for possible faults which can be caused by harsh environment. There are several fault test methods and related issues to be standardized.
Semiconductor devices used in automotive vehicles are exposed in harsh environment of very high or very low temperature, vibration, high frequency signals, etc. Therefore, they are tested for possible faults which can be caused by harsh environment Evaluation results following this fault test methods will provide robustness of the semiconductor device.

IEC 62047-42:2022 specifies measuring methods of electro-mechanical conversion characteristics of piezoelectric thin film on microcantilever, which is typical structure of actual micro sensors and micro actuators. In order to obtain actual and precise piezoelectric coefficient of the piezoelectric thin films with microdevice structures, and this document reports the schema to determine the characteristic parameters for consumer, industry or any other applications of piezoelectric devices. This document applies to piezoelectric thin films on microcantilever fabricated by MEMS process.

IEC 63068-4:2022(E) provides a procedure for identifying and evaluating defects in as-grown 4H-SiC (Silicon Carbide) homoepitaxial wafer by systematically combining two test methods of optical inspection and photoluminescence (PL). Additionally, this document exemplifies optical inspection and PL images to enable the detection and categorization of defects in SiC homoepitaxial wafers.

IEC 63275-2:2022 gives the test method and a procedure using this method to evaluate the on-state voltage change, on-state resistance change and reverse drain voltage change of silicon carbide (SiC) power MOSFET devices due to body diode operation. This test is not generally requested for Si power transistors.

IEC 60749-10:2022 is intended to evaluate devices in the free state and assembled to printed wiring boards for use in electrical equipment. The method is intended to determine the compatibility of devices and subassemblies to withstand moderately severe shocks. The use of subassemblies is a means to test devices in usage conditions as assembled to printed wiring boards. Mechanical shock due to suddenly applied forces, or abrupt change in motion produced by handling, transportation or field operation can disturb operating characteristics, particularly if the shock pulses are repetitive. This is a destructive test intended for device qualification.
This edition cancels and replaces the first edition published in 2002. This edition includes the following significant technical changes with respect to the previous edition:
covers both unattached components and components attached to printed wiring boards;
tolerance limits modified for peak acceleration and pulse duration;
mathematical formulae added for velocity change and equivalent drop height.

IEC 63275-1:2022 gives a test method to evaluate gate threshold voltage shift of silicon carbide (SiC) power metal-oxide-semiconductor field-effect transistors (MOSFETs) using room temperature readout after applying continuous positive gate-source voltage stress at elevated temperature. The proposed method accepts a certain amount of recovery by allowing large delay times between stress and measurement (up to 10 h).

IEC 63284:2022 covers the protocol of performing a stress procedure and a corresponding test method to evaluate the reliability of gallium nitride (GaN) power transistors by inductive load switching, specifically hard-switching stress