Integrated heater and temperature measuring device

Abstract

This specification discloses an integrated heater and measuring (IHM) device comprising thermal sensing elements and thermal sensing circuits. The thermal sensing elements generate heat to determine the temperature of the IHM device. In some embodiments, the thermal sensing elements may operate in multiple modes, namely a heating mode, a sensing mode, and / or an off mode. A controller may dynamically adjust the characteristics of the operating mode and / or duration based on the determined temperature. The adjusted characteristics may include the duration of the heating mode, the on-time of the thermal sensing elements, etc. The controller may adjust the duration of the heating mode based on the temperature difference between the determined temperature and a set temperature. For example, the duration of the heating mode may be reduced when the temperature difference is small, and increased when the temperature difference is large.

Description

Technical Field

[0001] Cross - reference to Related Applications This application claims the benefit of U.S. Provisional Patent Application No. 18 / 311,164, filed on May 2, 2023, the entire content of which is incorporated herein by reference for all purposes.

[0002] This disclosure relates to a heating and temperature measurement system for electrically testing integrated circuit devices.

Background Art

[0003] Testing integrated circuit (IC) devices involves heating the device using a heater to bring it to a set temperature during testing. In some cases, it is desirable to accurately measure the heater temperature. The measured temperature is used to actively control the heater. Inaccurate measurement of the heater temperature can lead to inaccurate IC temperatures, which can result in variability in the performance of the device under test (DUT) or premature failure. In some cases, the temperature sensor used to measure the heater temperature is a separate component installed in close proximity to the heater. However, there are several disadvantages when the temperature sensor is separate from the heater. A separate temperature sensor may not be able to accurately measure the heater temperature. This inaccurate measurement may be due to the separate temperature sensor not being close enough to the heater, resulting in, for example, an undesirable delay between the change in heater temperature and the measured temperature. This undesirable delay is due to the need for heat to be transferred through the path from the heater to the sensor. This undesirable delay is also due to the thermal mass of the separate temperature sensor, which increases the delay between the actual temperature and the measured temperature. Furthermore, separate temperature sensors can complicate the physical design and layout of the test system, especially in test systems using multiple heaters and temperature sensors, requiring additional circuitry such as dedicated temperature sensing traces and I / O pins. Additionally, separate temperature sensors can introduce additional failure modes. For example, a temperature sensor failure may not be recognized as a failure, and corrective actions to adjust the heater output may not be taken. An integrated heater and temperature sensor that avoids these drawbacks is needed. [Overview of the project] [Means for solving the problem]

[0004] This specification discloses an integrated heater and measuring (IHM) device comprising one or more thermal sensing elements. The thermal sensing element may be configured to both generate heat and determine the temperature of the IHM device, resulting in a simpler, better manufacturing yield, smaller, and fewer-pin IHM device than a heater. In some embodiments, the thermal sensing element may operate in multiple modes, namely a heating mode, a sensing mode, and / or an off mode. A controller may dynamically adjust the characteristics of the thermal sensing element based on the determined temperature. The adjusted characteristics may include the duration of the heating mode, the on-time of the thermal sensing element, etc. This dynamic adjustment of characteristics may enable the IHM device to heat the device under test faster than a heater. In some embodiments, the IHM comprises one or more thermal sensing circuits to control the operation of the thermal sensing element(s). For example, controlling operations such as supplying power to the thermal sensing element(s) and determining the voltage drop across the thermal sensing element(s).

[0005] A method for controlling the temperature of a device under test is disclosed. The method includes, during the heating mode of a thermal sensing element, using a controller to send one or more control signals to a drive voltage circuit and using the drive voltage circuit to generate power supplied to the thermal sensing element; during the sensing mode of the thermal sensing element, using a current circuit to supply current to the thermal sensing element, using a sense circuit to determine a voltage drop across the thermal sensing element, and using a controller to determine the temperature of the device under test based on the current and voltage drop, wherein the thermal sensing element operates in heating mode and sensing mode for different parts of a period. Additionally or alternatively, in some embodiments, determining the temperature of the device under test includes determining the resistance of the thermal sensing element based on the current and voltage drop, and the temperature of the device under test is related to the determined resistance. Additionally or alternatively, in some embodiments, the duration of the heating mode changes dynamically based on the difference between the determined temperature and the set temperature. Additionally or alternatively, in some embodiments, the duration of the sensing mode is predetermined. Additionally or alternatively, in some embodiments, the thermal sensing element operates in off mode for part of a period. Additionally or alternatively, in some embodiments, the method further includes dynamically adjusting the characteristics of the heating mode based on the determined temperature. Additionally or alternatively, in some embodiments, adjusting the characteristics of the heating mode includes reducing the duration of the heating mode when the temperature difference between the determined temperature and the set temperature is low, increasing the duration of the heating mode when the temperature difference between the determined temperature and the set temperature is high, or maintaining the duration of the heating mode when the temperature difference between the determined temperature and the set temperature is zero. Additionally or alternatively, in some embodiments, the duration is 200 μs. Additionally or alternatively, in some embodiments, the thermal sensing element is included in multiple thermal sensing elements of an integrated heater and temperature measuring device, and the multiple thermal sensing elements operate simultaneously in sensing mode. Additionally or alternatively, in some embodiments, the thermal sensing element is included in multiple thermal sensing elements of an integrated heater and temperature measuring device, and the multiple thermal sensing elements operate simultaneously in off mode.In addition or alternatively, in some embodiments, the method further includes determining whether one or more criteria are met, including that the determined temperature of the device under test is greater than a temperature threshold, the power of the device under test is greater than a power threshold, the thermal sensing element is short-circuited, or the thermal sensing element is open-circuited. In addition or alternatively, in some embodiments, the method further includes preventing the drive voltage circuit from supplying power to the thermal sensing element during the heating mode of the thermal sensing element, in accordance with the meeting of one or more criteria.

[0006] An integrated heater and temperature measuring device is disclosed. The integrated heater and temperature measuring device comprises one or more thermal sensing elements and one or more thermal sensing circuits configured to operate in heating mode and sensing mode during different parts of a period, at least one of the one or more thermal sensing circuits comprising a drive voltage circuit configured to supply power to one or more thermal sensing elements to generate heat during heating mode, a current circuit configured to send current to the corresponding thermal sensing elements during sensing mode, a sensing voltage circuit configured to determine a voltage drop across the corresponding thermal sensing elements, and a controller configured to determine the temperature of the corresponding thermal sensing elements based on the voltage drop. Additionally or alternatively, in some embodiments, the integrated heater and temperature measuring device further comprises one or more sets of pins, the number of which is equal to the number of thermal sensing elements. Additionally or alternatively, in some embodiments, the integrated heater and temperature measuring device further comprises: a first layer of insulating material, on which at least one thermal sensing element is disposed; a second layer of insulating material disposed on at least one thermal sensing element; a shield disposed on the second layer of insulating material; and a third layer of insulating material disposed on the shield. Additionally or alternatively, in some embodiments, one or more thermal sensing elements include: a first thermal sensing element configured to heat a first zone of the device under test and determine the temperature of the first zone; and a second thermal sensing element configured to heat a second zone of the device under test and determine the temperature of the second zone. Additionally or alternatively, in some embodiments, one or more thermal sensing elements include at least one controller that dynamically adjusts one or more characteristics of a heating mode, sensing mode, duration, or combination thereof based on the determined temperature. Additionally or alternatively, in some embodiments, one or more thermal sensing circuits are coupled to one or more thermal sensing elements using a four-wire connection. Additionally or alternatively, in some embodiments, each of the four-wire connections comprises wiring coupled to a two-wire connection, and each of the two-wire connections branches out to the outside of each thermal sensing element.Additionally or alternatively, in some embodiments, each of the four-wire connections comprises wiring coupled to a two-wire connection, and each of the two-wire connections branches into the interior of each thermal sensing element. Additionally or alternatively, in some embodiments, the zone corresponding to each thermal sensing element is smaller than the thermal sensing element itself. Additionally or alternatively, in some embodiments, the controller is further configured to determine whether one or more criteria are met, one or more of which include the determined temperature of the device under test being greater than a temperature threshold, the power of the device under test being greater than a power threshold, the thermal sensing element being short-circuited, or the thermal sensing element being open-circuited. Additionally or alternatively, in some embodiments, one or more thermal sensing circuits comprises a fail-safe circuit configured such that, in accordance with the meeting of one or more criteria, the drive voltage circuit does not supply power to the thermal sensing element during the heating mode of the thermal sensing element.

[0007] It is recognized that any of the variations, aspects, features, and options described with respect to the system and method are equally applicable to this method, and vice versa. It is also clear that one or more of the above variations, aspects, features, and options can be combined. It should be understood that the present invention is not limited to the purposes described above, but may also include other purposes, including those recognizable to those skilled in the art. [Brief explanation of the drawing]

[0008] [Figure 1] A cross-sectional view of an exemplary heater is shown.

[0009] [Figure 2A] An exemplary cross-sectional view of an integrated heater and temperature measuring (IHM) device according to an embodiment of the present disclosure is shown.

[0010] [Figure 2B] This document shows an exemplary stacked structure of an IHM device according to an embodiment of the present disclosure.

[0011] [Figure 3]A block diagram of an exemplary circuit of a heat sensing element, according to an embodiment of the present disclosure, is shown.

[0012] [Figure 4] Examples of the period and mode of operation of a heat sensing element, according to an embodiment of the present disclosure, are shown.

[0013] [Figure 5A] An exemplary method for heating using a heat sensing element in heating mode, according to an embodiment of the present disclosure, is shown.

[0014] [Figure 5B] An exemplary method for determining the temperature of a heat sensing element in sensing mode, according to an embodiment of the present disclosure, is shown.

[0015] [Figure 6] A and B show a block diagram of an example of a four-wire connection for coupling a heat sensing circuit to a heat sensing element, according to an embodiment of the present disclosure.

[0016] [Figure 7] A block diagram of an exemplary heater, according to an embodiment of the present disclosure, is shown.

[0017] [Figure 8] A block diagram of an exemplary controller, according to an embodiment of the present disclosure, is shown.

[0018] [Figure 9] A block diagram of an exemplary computer used for one or more controllers, according to an embodiment of the present disclosure, is shown.

MODE FOR CARRYING OUT THE INVENTION

[0019] It is recognized that any of the variations, aspects, features, and options described with respect to the system apply equally to the method, and vice versa. It is also clear that any one or more of the above variations, aspects, features, and options can be combined.

[0020] This specification discloses an integrated heater and measurement (IHM) device including one or more thermal sensing elements. The thermal sensing element may be configured to generate heat and determine the temperature of the IHM device. In some embodiments, the thermal sensing element may operate in multiple modes, namely, a heating mode, a sensing mode, and / or an off mode. The controller may dynamically adjust the characteristics of the operating mode and / or period based on the determined temperature. The adjusted characteristics may include the duration of the heating mode, the on-time of the thermal sensing element, etc. In some embodiments, the controller may adjust the duration of the heating mode based on the temperature difference between the determined temperature and the set point. When the temperature difference is low, the controller may decrease the duration of the heating mode. When the temperature difference is high, the controller may increase the duration of the heating mode. When there is little temperature difference, the controller may maintain the duration of the heating mode.

[0021] In some embodiments, the IHM includes one or more thermal sensing circuits. The thermal sensing circuit is configured to control the thermal sensing element(s). The thermal sensing circuit may include a drive voltage circuit configured to provide power to the thermal sensing element(s) during the heating mode, a current circuit configured to send current to the thermal sensing element(s) during the sensing mode, a sense voltage circuit configured to determine one or more voltage drops across the thermal sensing element(s), and a controller configured to determine the temperature of the thermal sensing element(s) based on the voltage drop(s). In some embodiments, the thermal sensing circuit(s) may include a fail-safe circuit configured such that the drive voltage circuit does not provide power to the thermal sensing element(s). In some embodiments, the thermal sensing circuit(s) is coupled to the thermal sensing element(s) using a two-wire connection or a four-wire connection.

[0022] The following descriptions are provided to enable those skilled in the art to create and use various embodiments. The descriptions of specific devices, methods, and applications are provided only as examples. These examples are provided solely to add context and aid in understanding the examples described. It will therefore be apparent to those skilled in the art that the examples described may be practiced without some or all of the specific details. The following examples should not be construed as limiting, as other applications are possible. Various modifications in the examples described herein will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other examples and applications without departing from the spirit and scope of the various embodiments. Therefore, the various embodiments are not intended to limit the scope to the examples described and shown herein, but will be given a scope consistent with the claims.

[0023] Various technical and process flow steps will be described in detail with reference to the examples shown in the accompanying drawings. The following description includes several specific details to provide a complete understanding of one or more embodiments and / or features described or referred to herein. However, it will be apparent to those skilled in the art that one or more embodiments and / or features described or referred to herein can be practiced without some or all of these specific details. In other examples, well-known process steps and / or structures are not described in detail so as not to obscure some of the embodiments and / or features described or referred to herein.

[0024] The following examples refer to the accompanying drawings, which form part of this specification, illustrating specific examples that can be implemented. It should be understood that other examples may be used and structural modifications may be made without departing from the scope of this disclosure.

[0025] The terms used in describing the various embodiments described herein are for the purpose of describing only specific embodiments and are not intended to be limiting. Where used in the descriptions of the various embodiments and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural form unless the context otherwise explicitly indicates. The terms "and / or" as used herein are also understood to refer to and encompass any possible combination of one or more of the items described relating. Furthermore, the terms "includes," "including," "comprises," and / or "comprising," when used herein, specify the presence of the described features, integers, steps, actions, elements, and / or components, but are not intended to exclude the presence or addition of one or more other features, integers, steps, actions, elements, components, and / or groups thereof.

[0026] Figure 1 shows a cross-sectional view of an exemplary heater. The heater 156 comprises a plurality of pins, a plurality of heating elements 163, a measurement trace 161, and a shield 167. Some of the plurality of pins 151 (including pins 151A and 151B), 153 (including pins 153A and 153B), and 155 (including pins 155A and 155B) may be pins used to carry current in and out of the heater 156. The plurality of heating elements 163 generate heat for the heater 156. The measurement trace 161 determines the temperature of a surface 159 that is in contact with a component such as a DUT. As shown in the figure, the measurement trace 161 is located inside the body of the heater 156 near the surface 159. The measurement trace 161 is separate from the heating elements 163 and is coupled to a pin 151 separate from pins 153 and 155 of the heating elements 163. A controller (not shown) is coupled to pins 151, 153, and 155, thereby enabling the controller to determine the temperature of heater 156 and adjust the temperature of the heater according to the determined temperature.

[0027] Figure 2A shows a cross-sectional view of an exemplary integrated heater and temperature measuring (IHM) device according to an embodiment of the present disclosure. The IHM device 256 comprises a plurality of pins, a plurality of thermal sensing elements 263A and 263B, and a shield 267. The thermal sensing elements 263A and 263B generate heat for the IHM device 256. At least one thermal sensing element 263A or 263B also determines the temperature of the IHM device 256, as will be described in more detail below. Thermal sensing element 263A is coupled to pin 253 (including pins 253A and 253B), and thermal sensing element 263B is coupled to pin 255 (including pins 255A and 255B). One or more controllers are coupled to pins 253 and 255 to operate the thermal sensing elements 263A and 263B and to perform both heating and temperature measuring of the IHM device 256. In the IHM device 256, separate measurement traces (e.g., measurement trace 161 in Figure 1) and separate pins (e.g., heating pins 153 and 155 as shown in Figure 1, and a separate pin 151 for measurement) are not required to heat and determine the temperature. Embodiments of the present disclosure provide a single set of pins for each heat sensing element 263 (the number of pin sets is equal to the number of heat sensing elements), eliminating the need for additional pins for temperature sensing. For example, sets of pins 253A and 253B are coupled to heat sensing element 263A, and sets of pins 255A and 255B are coupled to heat sensing element 263B. Heat sensing element 263A heats a first portion (e.g., a first zone) of the IHM device 256 and determines its temperature, and heat sensing element 263B heats a second portion (e.g., a second zone) and determines its temperature. As a result, the IHM device 256 is simpler (e.g., than heater 156 in Figure 1) and improves manufacturing yield. Furthermore, the IHM device 256 is small even with a certain number of heat sensing elements, making it possible to include smaller heaters or additional pins and / or heat sensing elements in a single IHM device 256. An IHM device 256 of an embodiment of the present disclosure having a certain number of heat sensing elements 263 has fewer pins than a heater having the same number of heating elements 163.For example, the heater 156 in Figure 1, which includes two heating elements, requires six pins, while the IHM device 256, which includes the same number of heat sensing elements 263, requires only four pins. In the case of test systems that include a large number of heating elements and / or temperature sensors, the number of pins and the resulting interconnection wiring can be large, resulting in bulky, expensive, and complex heaters, thermal heads, and test systems. As technology advances, components are becoming denser and more complexly mixed, and it may be important that the test system can handle thermal control components located within close proximity to each other. Therefore, bulky, expensive, and complex heaters, thermal heads, and test systems may not be suitable.

[0028] In some embodiments, the thermal sensing element 263 includes a resistor and / or a resistance trace. Examples of materials for the thermal sensing element 263 may include, but are not limited to, tungsten, iron, Kovar, molybdenum, palladium, platinum, or combinations thereof. In some embodiments, the thermal sensing element 263 may have a temperature coefficient of resistance (TCR) similar to that of the measurement trace 161 in Figure 1. For example, the thermal sensing element 263 may have a TCR of 0.0031 ppm / °C ± 20%. While a lower TCR may yield better results when the heater has a heating element separate from the temperature sensor, here a high TCR of the thermal sensing element may help detect small temperature changes. At a high TCR, a large change in resistance may indicate a small temperature change. Thus, the IHM device 256 of this disclosure may be more sensitive than the heater 156 (in Figure 1).

[0029] The controller may transmit one or more signals (e.g., current or voltage signals) to pins 253 and 255 to power the thermal sensing elements 263A and 263B. Power applied to pins 253A and 253B may turn on the electrically coupled thermal sensing element 263A, generating heat, and power applied to pins 255A and 255B may turn on the electrically coupled thermal sensing element 263B, generating heat. In some embodiments, the IHM device 256 includes a number of thermal sensing elements 263 to increase the total power output from the IHM device 256 at a given voltage. For example, the IHM device 256 may include five thermal sensing elements 263, each configured to generate 200W at 200VDC, thereby generating a total output power of 1000W. In some embodiments, as will be described in more detail below, the controller determines the resistance of the thermal sensing element 263 and then determines its temperature based on the determined resistance.

[0030] In some embodiments, the thermal sensing elements 263A and 263B may be formed on the same layer as shown in the figure. Alternatively, the thermal sensing elements 263A and 263B may be formed on separate layers within the body of the IHM device 256. For example, the thermal sensing elements 263A and 263B may be resistor traces formed on multiple layers, thereby acquiring a target resistance within the target region of the IHM device 256. In some embodiments, the thermal sensing elements 263A and 263B are located further from the DUT 202 than the shield 267.

[0031] Figure 2A shows a single row of four pins, but embodiments of the present disclosure may include any configuration and any number of pins, for example, a single row of pins arranged around the surface of the IHM device 256, two pins arranged in a row on one side of the IHM device 256, ten or more pins arranged in a row, or four pins arranged in two rows on two sides. In some embodiments, the number of pins may occupy less than 10%, less than 30%, less than 50%, etc., of the surface of the IHM device 256. In some embodiments, the pins may be excluded in the inner region of the surface 258 of the IHM device 256, thereby allowing the IHM device 256 to contact the adapter in the inner region.

[0032] In some embodiments, the shield 267 is located closer to the DUT 202 than the thermal sensing element 263, for example, as shown in the exemplary laminated structure of Figure 2B. The laminated structure 213 comprises a first layer of insulating material 204 located (in order) on the surface 259 of the IHM device 256, a shield 267 disposed on the first layer of insulating material 204, a second layer of insulating material 214 disposed on the shield 267, a thermal sensing element(s) 263 disposed on the second layer of insulating material 214, and a third layer of insulating material 224 disposed on the thermal sensing element(s) 263. In some embodiments, the first layer of insulating material 204 is located between the shield 267 and the DUT 202 (or as an intermediate layer(s) between the thermal sensing element(s) 263 and the DUT 202. The insulating material of the first layer, the second layer, and / or the third layer may be a substrate. The substrate may include, for example, ceramic or aluminum nitride (AlN).

[0033] Shield 267 may be grounded and provides an electrical grounding path to the IHM device 256 during testing. As described in more detail below, during testing, the thermal sensing element 263 is continuously switched on and off with high voltage and high current, which may generate electrical noise. Electrical noise may interfere with the circuitry and / or measurements of the test system. Shield 267 reduces or eliminates unwanted electrical noise.

[0034] The test system may comprise one or more thermal heads. Each zone of the thermal head may include one or more thermal sensing elements 263. In some embodiments, any number of thermal sensing elements 263 may be associated with a zone, depending on the power requirements of the zone and the power limitations of the thermal sensing elements 263. As a non-limiting example, each thermal sensing element 263 heats its own zone and senses its temperature. In some embodiments, the first thermal sensing element 263A is independent of the second thermal sensing element 263B so that when heating the first zone (using the first thermal sensing element 263A), the second zone is not heated, and vice versa. Additionally or alternatively, the temperature and / or resistance determined for the first zone (using the first thermal sensing element 263A) is not affected by the second zone.

[0035] The total area of ​​thermal control may be equal to or less than the total surface area of ​​the IHM device 256 (e.g., 20% of its total surface area). In some embodiments, the thermal sensing elements 263 are located across a high percentage (e.g., 80% or more) of the surface of the IHM device 256, or across an entire specific zone 263 of the IHM device 256. In some embodiments, different thermal sensing elements 263 may have different characteristics. For example, one or more first thermal sensing elements 263A may be associated with one or more first zones, each being a high-power thermal sensing element and a high-power zone, while one or more second thermal sensing elements and second zones may be low-power thermal sensing elements and low-power zones, respectively.

[0036] Embodiments of the present disclosure include a thermal sensing element 263 having a different material, resistance, and / or TCR from another thermal sensing element 263 within a given IHM device 256. In some embodiments, the IHM device 256 comprises one or more insulating mechanisms that isolate two or more thermal sensing elements 263 or multiple zones from each other, or the thermal sensing elements 263 or multiple zones may be spatially separated by a predetermined distance. One exemplary insulating mechanism includes a through-hole or groove in the body of the IHM device 256 at a position(s) between the thermal sensing element and the edge(s) of the zone. In some embodiments, different thermal sensing elements 263 are associated with different zones.

[0037] Figure 3 shows a block diagram of an exemplary circuit of a thermal sensing element according to an embodiment of the present disclosure. The thermal sensing circuit 300 comprises a circuit for operating the thermal sensing element 263 in a plurality of operating modes, namely, a heating mode, a detection mode, and an off mode. The thermal sensing circuit 300 comprises a drive voltage circuit 363, a controller 302, a forced current circuit 365, a detection voltage circuit 364, and a fail-safe circuit 367. The drive voltage circuit 363 may be coupled to the controller 302, the fail-safe circuit 367, and node 375 of the thermal sensing element 263. The drive voltage circuit 363 is configured to receive one or more control signals 312 from the controller 302 and turn on the thermal sensing element 263, generating heat in the thermal sensing element 263 during the heating mode. The drive voltage circuit 363 may operate according to one or more control signals 312, such as turning off the thermal sensing element 263 so that the thermal sensing element 263 does not generate heat (for example, during the detection mode or off mode).

[0038] A forced current circuit 365 may be coupled to the controller 302 and to node 375 of the thermal sensing element 263. The forced current circuit 365 provides a current signal to the thermal sensing element 263 during sensing mode in response to one or more control signals 312 from the controller 302. The current signal from the forced current circuit 365 causes current to flow through the thermal sensing element 263. A sensing voltage circuit 364, coupled to both nodes 373 and 375 of the thermal sensing element 263, determines the voltage drop across nodes 373 and 375 and generates a voltage signal 313 indicating this voltage drop. The voltage signal 313 is processed (including, for example, conversion by an analog-to-digital converter, amplification, etc.) and transmitted to the controller 302. Those skilled in the art will understand that the controller may be implemented in hardware or software.

[0039] In some embodiments, the thermal sensing circuit 300 includes a fail-safe circuit 367. The fail-safe circuit 367 is configured to reduce the likelihood of one or more thermal sensing elements 263 overheating and / or failing, or to prevent them from overheating and / or failing. In some cases, a thermal sensing element 263 may be inadvertently short-circuited to earth. If there is a short-circuit to earth, the controller 302 determines that the resistance of the thermal sensing element 263 is lower than its actual resistance. The controller 302 may also determine that the temperature of the thermal sensing element 263 is lower than its actual temperature, and thus the controller 302 may attempt to increase the power to the thermal sensing element 263 (if there is no fail-safe circuit 367). Excess power may cause the thermal sensing element 263 to generate too much heat and fail. The fail-safe circuit 367 prevents the supply of excess power to the thermal sensing element 263, for example, during heating mode. In some embodiments, the fail-safe circuit 367 and / or controller 302 may determine that one or more criteria are not met and prevent the drive voltage circuit 363 from supplying voltage to the thermal sensing element 263. Exemplary criteria, but not limited to, include, the DUT's temperature being greater than a temperature threshold, the DUT's power being greater than a power threshold, the thermal sensing element 263 being short-circuited, or the thermal sensing element 263 being open-circuited. For example, the controller 302 may determine that a criterion is not met and, in response, an error may occur, which is then transmitted to the fail-safe circuit 367. In some embodiments, the fail-safe circuit 367 includes a fuse that, if the thermal sensing element 263 is short-circuited, will fail and / or open-circuit.

[0040] The controller 302 determines the temperature of the thermal sensing element 263 based on the voltage signal 313 and the current signal from the forced current circuit 365. In some embodiments, the controller 302 includes an FPGA. Using an FPGA for thermal control can be beneficial due to the accuracy of the time reference, or the level of precision depending on the frequency used for timing. Any variation in the time reference distorts the "D" or derivative term in the PID algorithm, introducing errors into the thermal control. Furthermore, FPGAs can support the very fast floating-point operations that may be required by the control algorithm. In addition, FPGAs can support high frequencies (e.g., a frequency of 5 kHz, or in other words, temperature measurements every 200 μs) for driving one or more control signals to the thermal sensing element 263. Faster temperature measurements allow for more precise control of the temperature of the thermal sensing element 263.

[0041] In some embodiments, the thermal sensing circuit 300 operates as a feedback loop. The thermal sensing circuit 300 causes the thermal sensing element 263 to generate heat during the heating mode. The thermal sensing circuit 300 also determines the resistance or temperature of the thermal sensing element 263 during the sensing mode. The characteristics of the thermal sensing circuit 300 during the heating mode are determined and / or dynamically adjusted based on the resistance or temperature determined during the sensing mode. The thermal sensing circuit 300 switches modes. In some embodiments, the period includes one part in which the thermal sensing circuit 300 operates in heating mode, one part in which the thermal sensing circuit 300 operates in sensing mode, and optionally one part in which the thermal sensing circuit 300 operates in off mode. In off mode, the thermal sensing element 263 does not generate heat and does not detect temperature. In some embodiments, each thermal sensing element 263 is associated with its own thermal sensing circuit 300.

[0042] Figure 4 shows an example of the operating period and mode of a thermal sensing element according to an embodiment of the present disclosure. The timing chart in the figure shows a plurality of periods 402. The thermal sensing circuit 300 may operate in one or more of periods 402A, 402B, or 402C.

[0043] The different periods 402A, 402B, and 402C shown in Figure 4 include different operating modes, different proportions of periods, etc., relative to a given operating mode. In some embodiments, the majority of period 402A includes the heating mode 422. For example, period 402A may include the heating mode 422 for 80% of period 402A, the off mode 432 for 10%, and the detection mode 412 for 10%. As another example, period 402B may include the heating mode 422 for 40% of period 402B, the off mode 432 for 50%, and the detection mode 412 for 10%. Period 402C includes the heating mode 422 for 90% and the detection mode 412 for 10%. In some embodiments, when a period includes the heating mode, the off mode, and the detection mode, the off mode follows the heating mode and the detection mode follows the off mode.

[0044] In some embodiments, the controller 302 may dynamically adjust the characteristics of the operating mode, such as the heating mode and / or duration, based on the determined temperature. The duration of the heating mode 422 (or the proportion of the period 402 occupied by the heating mode 422) may be dynamically changed and adjusted, for example, based on the temperature difference between the measured temperature and the set temperature (for example, it may be changed in real time). If the temperature difference is greater than a differential threshold (for example, if the difference between the measured temperature and the set temperature is large), the controller 302 turns on the thermal sensing element 263 in heating mode 422.

[0045] If the temperature difference is within the range of a differential threshold (for example, if the measured temperature is close to the setpoint temperature), the controller 302 determines the on-time of the thermal sensing element 263, where the on-time may be the time required to maintain the temperature of the thermal sensing element 263. In some embodiments, the controller 302 determines the on-time based on a PID (proportional, integral, derivative) control algorithm. For example, the temperature of the thermal sensing element 263 (determined during sensing mode) may be lower than the setpoint temperature by a certain (first) temperature difference. The controller 302 sets or adjusts the duration of the heating mode based on the first temperature difference. If there is a different second temperature difference in the temperature of the thermal sensing element 263, the controller 302 adjusts the duration of the heating mode according to the second temperature difference. In one non-limiting example, since the second (lower) temperature difference is lower than the first (higher) temperature difference, the controller 302 reduces the duration for which the thermal sensing element 263 is generating heat when the amount of heat generated is low. When there is a large temperature difference between the determined temperature and the set temperature, the controller 302 increases the duration for which the heat sensing element 263 generates heat (the duration of the heating mode) when the amount of heat generated is large. For example, the heat sensing circuit 300 operates according to a period 402C with a large temperature difference, a period 402B with a small temperature difference, and a period 402A where the temperature difference is in between. In some embodiments, the controller 302 is configured to maintain the temperature of the heat sensing element 263 over one or more periods. In some embodiments, the controller 302 maintains the duration and / or percentage of the operating mode while the temperature difference is zero.

[0046] During heating mode 422, the thermal sensing element 263 may operate by modulating an on-pulse. In some embodiments, the duty cycle of the on-pulse may be based on the temperature difference between the measured temperature and the set temperature, or whether the measured temperature is higher or lower than the set temperature. For example, when the measured temperature is below the set temperature, the duty cycle of the on-pulse may be 90% (as a result, the thermal sensing element 263 can heat the DUT quickly). In another example, when the measured temperature is higher than the set temperature, the duty cycle of the on-pulse may be 0% (as a result, the thermal sensing element 263 may allow the cooling plate to cool the DUT).

[0047] In some embodiments, period 402C may not include off-mode 432. During off-mode 432, in some embodiments, the drive voltage circuit 363, the forced current circuit 365, and the sensing voltage circuit 364 are off. In some embodiments, the duration of sensing mode 412 is predetermined. The controller 302 determines the proportion of different operating modes and / or periods for a given operating mode.

[0048] In some embodiments, the IHM device 256 and / or test system comprises a plurality of thermal sensing elements 263 and a plurality of thermal sensing circuits 300. For example, the IHM device 256 includes 16 thermal sensing elements 263 and 16 thermal sensing circuits 300. When operating a thermal sensing element 263 in off mode 432 and / or sensing mode 412, in some embodiments, other thermal sensing elements 263 (e.g., the remaining 15 thermal sensing elements 263 out of 16) also operate in the same mode. Operating multiple (e.g., all) thermal sensing elements 263 of the same IHM device 256 simultaneously in the same mode (sensing mode, off mode, etc.) may help reduce or eliminate noise resulting from switching of the thermal sensing circuits 300, for example.

[0049] In some embodiments, the voltage measured by the sensing voltage circuit 364 is susceptible to noise from the thermal sensing circuit 300. This noise can interfere with the accuracy of the determined resistance and / or temperature. This is particularly problematic for high-voltage heaters (voltages greater than 200V, e.g., 240V), which generate large EMI events when switched on and / or when fine temperature control is required. For example, in some applications, it is desirable or required that the sensing voltage circuit 364 be able to measure changes of an order of magnitude in mV. To mitigate potential noise due to heater switching, embodiments of the present disclosure include measuring the temperature of the thermal sensing element 263 in sensing mode over a period of time different from the heating mode. The period 402 may include multiple operating modes of the thermal sensing element 263. In some embodiments, the period 402 may be determined based on the frequency of temperature measurements. For example, the IHM device 256 of the present disclosure may measure the temperature of the thermal sensing element every 200 μs, and the period may be 200 μs.

[0050] Embodiments of the present disclosure include methods for controlling the temperature of the DUT. Figure 5A shows an exemplary method for using a heated thermal sensing element according to an embodiment of the present disclosure. To heat the thermal sensing element 263, the controller 302 transmits one or more control signals 312 to the drive voltage circuit 363 (step 502 of Method 500). The drive voltage circuit 363 generates and provides power to the thermal sensing element 263 (step 504). The power turns on the thermal sensing element 263 (step 506). In some embodiments, the amount of power can be based on the duty cycle of the on-pulse of the thermal sensing element 263. Next, in step 508, the thermal sensing element 263 generates heat, the amount of heat generated is related to the power applied by the drive voltage circuit 363. One or more devices under test 202 are thermally coupled to the IHM device 256, and therefore the thermal sensing element 263 of the IHM device 256 heats one or more devices under test 202 (step 510).

[0051] Figure 5B shows an exemplary method for determining the temperature of a thermal sensing element in sensing mode according to an embodiment of the present disclosure. Method 550 includes step 552, in which the controller 302 transmits one or more control signals 312 to a current circuit (e.g., a forced current circuit 365). In step 554, the forced current circuit 365 generates a current (e.g., a fixed forced current) and sends it to the thermal sensing element 263. In some embodiments, the forced current circuit 365 sends the fixed forced current to node 375 of the thermal sensing element 263. The current passing through the thermal sensing element 263 causes a voltage drop across the thermal sensing element 263 (step 556). In step 558, a sense circuit (e.g., a sense voltage circuit 364) determines the voltage (e.g., a voltage drop) across nodes 373 and 375 of the thermal sensing element 263. The sense voltage circuit 364 generates a voltage signal 313 indicating the measured voltage (step 560). Next, the voltage signal 313 is output to the controller 302. In step 562, the controller 302 receives the voltage signal 313 and determines the resistance of the thermal sensing element 263. In some embodiments, the resistance of the thermal sensing element 263 is determined based on the measured voltage (from the sensing voltage circuit 364) and the generated current (from the forced current circuit 365). In some embodiments, in step 564, the controller 302 determines the temperature of the thermal sensing element 263 based on its resistance. In some embodiments, step 563 includes using a resistance-temperature relationship, which may be determined or adjusted based on calibration information.

[0052] In some embodiments, calibration information is determined after the IHM device 256 is manufactured. Multiple resistances of the thermal sensing element 263 are measured at different temperatures to generate predetermined calibration information, such as a calibration curve, calibration table, or related relationship between resistance and temperature. Embodiments of the present disclosure include, but are not limited to, multiple calibration data, including thermal sensing element calibration data and printed circuit assembly calibration data. The thermal sensing element calibration data may be stored, for example, in a non-volatile memory chip, or coded in a 1D or 2D code (e.g., a standard barcode or a 2D matrix barcode), or in a remote database. In some embodiments, a printed circuit assembly (PCA) is associated with the IHM device 256. The PCA may have specific characteristics and relationships with respect to temperature. The PCA may have its own set of calibration data, distinct from the thermal sensing element calibration data. The PCA calibration data may be stored in a non-volatile memory chip, or coded in a 1D or 2D code or in a remote database. The controller 302 can determine the measurement temperature of the IHM device 256, or the temperature of one or more zones of the IHM device 256, using predetermined calibration information. Based on the determined temperature(s), the controller 302 controls one or more thermal sensing elements 263 accordingly.

[0053] In some embodiments, when the test system is powered on, the controller 302 reads calibration data for the relevant thermal sensing element 263 from non-volatile memory. The controller 302 combines the thermal sensing element calibration data with PCA calibration data to generate a resistance-temperature relationship for a given combination of thermal sensing element and PCA. In a non-limiting example, the resistance-temperature relationship may be linear. For example, this resistance-temperature relationship may be in the form of a slope with offset correction.

[0054] In some cases, the current and resistance characteristics of the connection between the thermal sensing element 263 and its associated thermal sensing circuit 300 may change over time. These changes can lead to unwanted temperature measurement errors. Embodiments of the present disclosure include a four-wire connection that eliminates temperature measurement errors due to resistance changes in the current sensing path. Figure 6A shows a block diagram of an example of a four-wire connection for coupling the thermal sensing circuit 300 to the thermal sensing element 263 according to an embodiment of the present disclosure. The thermal sensing element 263A is coupled to pins 253A and 253B (in Figure 2A), which may include, for example, a two-wire connection. In some embodiments, the four-wire connection is formed by coupling wiring 677 to the two-wire connection at pad 671, and then forming wiring 675 by branching each connection. In some embodiments, the connection branches out to the outside of the thermal sensing element 263A. Wires 675 and 677 provide electrical connections between the thermal sensing element 263A and the forced current circuit 365, and between the thermal sensing element 263A and the sensing voltage circuit 364. In some embodiments, wire 677 is coupled to pad 671 via a solder connection. There may be little current in the connection to the sensing voltage circuit 364. This makes it possible to perform stable voltage measurements, resulting in little decrease in current resistance.

[0055] In some embodiments, each two-wire connection branches inside the thermal sensing element 263B, as shown in Figure 6B. Wiring 675 connects to pad 671 inside the thermal sensing element 263B. In such cases, the thermal sensing element 263B is coupled to four pins (e.g., pins 253A, 253B, 255A, and 255B in Figure 2A) to electrically couple to the forced current circuit 365 and the sensing voltage circuit 364. In some embodiments, a four-wire connection is formed by coupling wiring 679 to a four-wire connection at pad 671. In some embodiments, the connection between the forced current circuit 365 and the corresponding pad 671 includes low resistance (mΩ or μΩ) so as to minimize the heat generated by the connection. This may be the case, for example, when the forced current is large (about 1A). In some embodiments, the resistance of the connection between the forced current circuit 365 and the corresponding pad 671 is lower than the resistance of the connection between the sensing voltage circuit 364 and the corresponding pad 671. High resistance may be permitted for the connection between the sensing voltage circuit 364 and the corresponding pad 671. This is because the resistance does not affect the sensing voltage or generate unwanted heat. The number of pads 671 may be greater than in the case of a four-wire connection with internal branching connections, although the exemplary four-wire connection with internal branching connections may be suitable, for example, when the corresponding zone is smaller than the thermal sensing element 263B, as shown in the figure.

[0056] Embodiments of the present disclosure include a heater comprising one or more thermal sensing elements, one or more heating elements, and one or more measurement traces. Figure 7 shows a block diagram of an exemplary heater according to an embodiment of the present disclosure. The heater 756 comprises a thermal sensing element 263, a heating element 163, and a measurement trace 161. The thermal sensing element 263 is configured to heat and measure temperature. The heating element 163 is configured to heat, and the measurement trace 161 is configured to measure the temperature of the heating element 163. The thermal sensing element 263 is coupled to pins 153A and 153B. The heating element 163 is coupled to pins 155A and 155B, and the measurement trace 161 is coupled to pins 151A and 151B.

[0057] Controller example

[0058] Figure 8 shows a block diagram of an exemplary controller 302 according to an embodiment of the present disclosure. The controller 302 comprises one or more components, including (but not limited to) an FPGA 875 (or similar), an A / D converter 881, and a D / A converter 883. The FPGA 875 may output one or more signals to the D / A converter 883, which then converts those signals (as described above) into a heater calibration signal 893 used to calibrate the thermal sensing element 263. The heater calibration signal 893 may contain calibration information, which in some embodiments may be used by the controller 302 to determine the measured temperature of the IHM device 256.

[0059] The A / D converter 881 converts the voltage signal 313 and then outputs the converted signal to the FPGA 875. The voltage signal 313 may indicate the voltage drop across the nodes of the thermal sensing element 263. The voltage signal 313 can be used to determine the measured temperature of the IHM device 256.

[0060] Furthermore, the FPGA 875 outputs one or more control signals 312 to control the drive voltage circuit 363 in order to generate power and supply power to the thermal sensing element 263 (as described above). In some embodiments, the FPGA 875 may transmit and / or receive external communication signals 883 to a controller (e.g., a higher-level system controller 902 in Figure 9).

[0061] Examples of computing systems

[0062] Figure 9 shows a block diagram of an exemplary computer 902 that may be used in connection with the disclosed heating and temperature measurement system according to embodiments of the present disclosure. The computer may be a machine, and a set of instructions within the machine may cause the machine to perform any one of the methods described herein, which may be performed according to embodiments of the present disclosure. In some embodiments, the machine may operate as a standalone device or may be connected to other machines (e.g., networked). In a networked configuration, the machine may operate as a server or client machine in a server-client network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. The machine may be a personal computer (PC), a tablet PC, a set-top box (STB), a personal digital assistant (PDA), a mobile phone, a web appliance, a network router, a switch or bridge, or any machine capable of executing (sequentially or otherwise) a set of instructions that specify an action to be taken by the machine. A mobile device may include an antenna, a chip for transmitting and receiving radio frequencies and wireless communications, and a keyboard. Furthermore, although only a single machine is given as an example, the term “machine” shall also be interpreted to include any collection of machines that individually or collectively execute a set (or set) of instructions in order to perform any one of the methods described herein.

[0063] An exemplary computer 902 includes a processor 904 (e.g., a central processing unit (CPU), a graphics processing unit (GPU), or both), memory 906 (e.g., read-only memory (ROM), flash memory, synchronous DRAM (SDRAM), and other dynamic random access memory (DRAM)), and static memory 908 (e.g., static random access memory (SRAM), etc.), which can communicate with each other via a bus 910.

[0064] The computer 902 may further include a video display 912 (e.g., a liquid crystal display (LCD) or a light-emitting diode (LED) display). The computer 902 also includes an alphanumeric input device 914 (e.g., a keyboard), a cursor control device 916 (e.g., a mouse), a disk drive unit 918, a signal generation device, a network interface device 922, and one or more wireless interface devices.

[0065] Furthermore, the computer 902 may include other inputs and outputs, including digital I / O and / or analog I / O. For example, the inputs and outputs may communicate with external devices such as chillers, pressure controllers, force controllers, and flow controllers using any type of communication protocol.

[0066] The drive unit 918 includes a machine-readable medium 920 in which a set of instructions 924 that embody one or more of the methods or functions described herein are stored. The software may also reside entirely or at least partially in the main memory 906 and / or the processor 904 while the computer 902 is executing its instructions, and the main memory 906 and the processor 904 also constitute the machine-readable medium. The software may also be transmitted or received over a network via a network interface device 922 and / or a wireless device.

[0067] Although the exemplary embodiments show the machine-readable medium 920 as a single medium, the term “machine-readable medium” should be interpreted to include a single or multiple mediums that store one or more sets of instructions (e.g., a centralized or distributed database, and / or associated caches and servers). The term “machine-readable medium” should also be interpreted to include any medium capable of storing, encoding, or carrying a set of instructions for execution by a machine, causing a machine to perform one or more of the methods of the present invention. Therefore, the term “machine-readable medium” should be interpreted to include, but are not limited to, solid-state memory, optical and magnetic media, and carrier signals.

[0068] While examples of this disclosure have been adequately illustrated with reference to the accompanying drawings, it should be noted that various changes and modifications will be apparent to those skilled in the art. Such changes and modifications should be understood to fall within the scope of examples of this disclosure as defined by the accompanying claims.

Claims

1. A method for controlling the temperature of a device under test, During the heating mode of the heat sensing element, Using a controller, one or more control signals are sent to the drive voltage circuit, Using the aforementioned drive voltage circuit, power is generated to be supplied to the thermal sensing element. During the detection mode of the aforementioned heat detection element, Using an electric current circuit, current is sent to the heat sensing element, Using a sense circuit, determine the voltage drop across the thermal sensing element, This includes determining the temperature of the device under test based on the current and voltage drop using the controller, The method wherein the heat sensing element operates in the heating mode and the sensing mode during different periods of time.

2. Determining the temperature of the device under test is, The method according to claim 1, comprising determining the resistance of the thermal sensing element based on the current and the voltage drop, wherein the temperature of the device under test is related to the determined resistance.

3. The method according to claim 1, wherein the duration of the heating mode changes dynamically based on the difference between the determined temperature and the set temperature.

4. The method according to claim 1, wherein the duration of the detection mode is predetermined.

5. The method according to claim 1, wherein the heat sensing element operates in off mode for part of the period.

6. The method according to claim 1, further comprising dynamically adjusting the characteristics of the heating mode based on the temperature determined above.

7. Adjusting the characteristics of the heating mode is If the temperature difference between the determined temperature and the set temperature is small, the duration of the heating mode is reduced. If the temperature difference between the determined temperature and the set temperature is high, increase the duration of the heating mode, or If the temperature difference between the determined temperature and the set temperature is zero, the duration of the heating mode is maintained. The method according to claim 6, including the method described in claim 6.

8. The method according to claim 1, wherein the period is 200 μs.

9. The method according to claim 1, wherein the heat sensing element is included in a plurality of heat sensing elements of an integrated heater and a temperature measuring device, and the plurality of heat sensing elements operate simultaneously in the detection mode.

10. The method according to claim 1, wherein the heat sensing element is included in a plurality of heat sensing elements of an integrated heater and a temperature measuring device, and the plurality of heat sensing elements operate simultaneously in off mode.

11. The method according to claim 1, further comprising determining whether one or more criteria are met, the one or more criteria being that the determined temperature of the device under test is greater than a temperature threshold, the power of the device under test is greater than a power threshold, the thermal sensing element is short-circuited, or the thermal sensing element is open-circuited.

12. The above method further, The method according to claim 1, comprising, in accordance with satisfying one or more of the above criteria, preventing the drive voltage circuit from supplying power to the heat sensing element during the heating mode of the heat sensing element.

13. An integrated heater and temperature measuring device, One or more thermal sensing elements configured to operate in heating mode and sensing mode during different parts of a period, It comprises one or more thermal detection circuits, and at least one of the one or more thermal detection circuits is A drive voltage circuit configured to supply power to one or more heat sensing elements to generate heat during the heating mode, A current circuit configured to supply current to the corresponding thermal sensing element during the aforementioned detection mode, A detection voltage circuit configured to determine the voltage drop across the corresponding thermal sensing element, A controller configured to determine the temperature of the corresponding heat sensing element based on the voltage drop, The integrated heater and temperature measuring device comprising the above.

14. The integrated heater and temperature measuring device according to claim 13, further comprising one or more sets of pins coupled to one or more heat sensing elements, wherein the number of sets of one or more pins is equal to the number of one or more heat sensing elements.

15. A first layer of insulating material, wherein at least one heat sensing element is disposed on the first layer of insulating material, A second layer of insulating material disposed on the at least one heat sensing element, A shield disposed on the second layer of the insulating material, A third layer of insulating material placed on the shield, The integrated heater and temperature measuring device according to claim 13, further comprising the above.

16. The one or more heat sensing elements described above are: A first thermal sensing element configured to heat a first zone of the device under test and determine the temperature of the second zone, A second thermal sensing element configured to heat a second zone of the device under test and to determine the temperature of the second zone, The integrated heater and temperature measuring device according to claim 13, comprising:

17. The integrated heater and temperature measuring device according to claim 13, wherein the one or more heat sensing elements comprises at least one controller that dynamically adjusts one or more characteristics of the heating mode, the sensing mode, the duration, or a combination thereof based on the determined temperature.

18. The integrated heater and temperature measuring device according to claim 13, wherein the one or more heat sensing circuits are coupled to the one or more heat sensing elements using a four-wire connection.

19. The integrated heater and temperature measuring device according to claim 18, wherein each of the four-wire connections is provided with wiring coupled to a two-wire connection, and each of the two-wire connections branches out to the outside of each of the heat sensing elements.

20. The integrated heater and temperature measuring device according to claim 18, wherein each of the four-wire connections is provided with wiring coupled to a two-wire connection, and each of the two-wire connections branches into the inside of each of the heat sensing elements.

21. The integrated heater and temperature measuring device according to claim 13, wherein the zone corresponding to each of the heat sensing elements is smaller than the heat sensing element.

22. The integrated heater and temperature measuring device according to claim 13, wherein the controller is further configured to determine whether one or more criteria are met, the one or more criteria being that the determined temperature of the device under test is greater than a temperature threshold, the power of the device under test is greater than a power threshold, the thermal sensing element is short-circuited, or the thermal sensing element is open-circuited.

23. The one or more heat sensing elements described above are: The integrated heater and temperature measuring device according to claim 22, further comprising a fail-safe circuit configured such that the drive voltage circuit does not supply power to the heat sensing element during the heating mode of the heat sensing element, in accordance with the fulfillment of one or more of the aforementioned criteria.

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