On-chip integrated infrared radiation source and its control method, semiconductor calibration device

Abstract

This application provides an on-chip integrated infrared radiation source and its control method, as well as a semiconductor calibration device, relating to the field of semiconductor testing technology. This application integrates a micro-emission unit array and a reference detection unit on a suspended membrane region. Each emission unit can self-heat and radiate under electrical drive, and is monitored in real time based on monitoring information. Drive control is performed according to a row-column interleaved addressing method, and adjustments are made based on initial drive parameters. This application not only achieves chip-level miniaturization and integration, reducing the volume and thermal inertia of traditional cavity blackbody radiation sources, but also improves the response speed of radiation output. The resonant cavity structure concentrates the radiation output into a preset wavelength band, improving compatibility with infrared temperature measurement equipment. The reference detection unit and peripheral circuits perform real-time monitoring and closed-loop adjustment of the array output, improving the stability of the radiation output. This is beneficial for high-precision calibration of infrared temperature measurement probes in semiconductor process equipment and facilitates integration into production line testing systems.

Description

Technical Field

[0001] This application relates to the field of semiconductor testing technology, and in particular to an on-chip integrated infrared radiation source and its control method, and a semiconductor calibration device. Background Technology

[0002] Standard radiation sources are crucial benchmarks for the traceability of infrared thermometry equipment. The accuracy, stability, and repeatability of their radiation output directly affect the temperature measurement accuracy and consistency of the device under test. Due to the complex operating conditions such as vacuum, plasma, and rapid temperature changes in semiconductor manufacturing processes, infrared standard radiation sources used for calibration typically need to possess characteristics such as a wide radiation temperature range, stable and traceable output, fast response speed, small size, and ease of integration into production line testing systems.

[0003] Currently, mainstream high-precision infrared standard radiation sources mainly employ blackbody radiation sources based on Planck's law. These sources heat or cool a high-emissivity cavity and use a built-in temperature sensor to perform closed-loop temperature control, outputting radiation equivalent to a blackbody at a specific temperature. However, traditional blackbody radiation sources generally suffer from problems such as large size, high thermal inertia, long time required to reach thermal equilibrium, and difficulty in rapid temperature changes. During mass production testing, switching between different temperature points often requires a long wait, resulting in low testing efficiency. Furthermore, fluctuations in ambient temperature can easily affect calibration accuracy.

[0004] Furthermore, existing technical solutions also struggle to meet the aforementioned application requirements. For instance, some integrated light source solutions typically employ a single wavelength output, whose operating band does not match the long-wave infrared response band commonly used in infrared temperature measurement equipment. Moreover, their design goals are primarily focused on online process monitoring rather than providing continuously adjustable and traceable standard radiation output. While some MEMS infrared light sources offer advantages in miniaturization and rapid response, they generally suffer from insufficient spectral matching, inadequate spatial uniformity control, lack of on-chip self-calibration capabilities, and unclear traceability paths. On the other hand, solutions combining discrete light sources, filters, and detectors suffer from system complexity, large size, low integration, and difficulties in production line deployment.

[0005] Therefore, existing technologies still lack an infrared standard radiation source that can simultaneously achieve miniaturization, fast response, target band matching, wide temperature range tunability, stable output, closed-loop calibration, and traceability of measurement values. Based on this, this application aims to provide an on-chip integrated infrared radiation source to solve the problems of large size, slow response, insufficient spectral matching, poor spatial uniformity, lack of self-calibration, and difficulty in achieving high-precision mass production calibration in existing technologies. Summary of the Invention

[0006] The purpose of this application is to provide an on-chip integrated infrared radiation source and its control method, as well as a semiconductor calibration device, to overcome the shortcomings of existing calibration devices, such as large size, slow response, insufficient spectral matching, poor spatial uniformity, lack of self-calibration, and difficulty in achieving high-precision mass production calibration.

[0007] Firstly, this application proposes an on-chip integrated infrared radiation source, comprising: A semiconductor substrate having a suspended film region formed by back-side release; A micro-emission unit array is formed on the suspended membrane region, comprising multiple emission units arranged in an array. Each emission unit is an independent infrared radiation source and adopts a metal-dielectric-metal Fabry-Perot resonant cavity structure. The metal-dielectric-metal Fabry-Perot resonant cavity structure includes a bottom metal layer that also serves as a heating resistor, a dielectric spacer layer, and a top metal layer. The thickness of the dielectric spacer layer is configured to enable the corresponding emission unit to resonate in a preset wavelength band. A reference detection unit is formed on the suspended membrane region and is used to acquire monitoring information of the micro-emission unit array, including temperature status and / or radiation status. The peripheral circuit is electrically connected to the micro-emitting unit array and the reference detection unit, respectively, and is used to process the output of the reference detection unit and drive the micro-emitting unit array according to the row-column interleaved addressing method; the peripheral circuit includes a storage unit, which is used to store the initial driving parameters of each of the transmitting units.

[0008] In one embodiment, the reference detection unit has the same layer structure as the transmitting unit.

[0009] In one embodiment, there are multiple reference detection units, each of which is disposed in the peripheral region and the central region of the micro-emission unit array.

[0010] In one embodiment, the number of reference detection units is six, with four reference detection units respectively disposed in the four corner regions of the micro-emission unit array, and two reference detection units disposed near the center of the micro-emission unit array.

[0011] In one embodiment, the bottom metal layer is patterned in a meandering shape to increase resistance and enable electrothermal conversion.

[0012] In one embodiment, the preset band range is 8–14 μm.

[0013] In one embodiment, the top metal layer is a semi-transparent metal film used to achieve infrared radiation emission and optical field oscillation within the resonant cavity.

[0014] Secondly, this application proposes a method for controlling an infrared radiation source, applicable to the on-chip integrated infrared radiation source described in any one of the first aspects, the method comprising: Obtain the target's equivalent blackbody temperature and its corresponding target monitoring value; Based on the target equivalent blackbody temperature, the initial driving parameters corresponding to each of the transmitting units are obtained by querying the storage unit. Based on the initial driving parameters, row and column gating signals and pulse width modulation signals are generated to control the micro-emitting unit array, so that each of the emitting units generates heat and outputs infrared radiation. The monitoring information of the reference detection unit is obtained, and the real-time monitoring value corresponding to the array radiation state is determined based on the monitoring information. The drive correction parameters are determined based on the deviation between the real-time monitored value and the target monitored value; The initial driving parameters are corrected based on the driving correction parameters to obtain the target driving parameters for each transmitting unit; The micro-emission unit array is subjected to closed-loop drive control based on the target driving parameters to output infrared radiation corresponding to the target's equivalent blackbody temperature.

[0015] In one embodiment, the step of querying the storage unit to obtain the initial driving parameters corresponding to each of the transmitting units based on the target equivalent blackbody temperature includes: Individual calibration data corresponding to each of the transmitting units can be retrieved from the storage unit; the individual calibration data includes at least one of the following: the correspondence between driving parameters and radiation intensity, the correspondence between driving parameters and equivalent radiation temperature, and the correspondence between resistance value and temperature; Based on the target equivalent blackbody temperature, interpolation is performed on the individualized calibration data corresponding to each of the transmitting units to obtain the initial driving parameters corresponding to each of the transmitting units. The initial driving parameters include at least one of driving voltage, driving current, and pulse width modulation duty cycle.

[0016] In one embodiment, the individualized calibration data is constructed during the pre-calibration phase, and the construction method includes: Within a preset temperature range, a traceable blackbody is used as a reference to calibrate each of the aforementioned emission units point by point. Record the correspondence between the driving parameters and the equivalent radiation temperature of each of the aforementioned emission units at multiple calibrated temperature points; Based on the correspondence, individualized calibration data corresponding to each of the transmitting units is constructed, and the individualized calibration data is written into the storage unit.

[0017] In one embodiment, generating row and column gating signals and pulse width modulation signals for controlling the micro-emission unit array based on the initial driving parameters includes: The micro-emission unit array is scanned according to a preset cycle and a preset sequence; For each selected row and / or column, a corresponding pulse width modulation signal is generated based on the initial driving parameters; The duty cycle of the pulse width modulation signal is determined based on the initial driving parameters to control the average heating power of each of the transmitting units and adjust the radiation intensity of each of the transmitting units.

[0018] In one embodiment, the monitoring information includes temperature monitoring data and radiation monitoring data; the reference detection unit operates in either temperature monitoring mode or radiation monitoring mode. The acquisition of the monitoring information of the reference detection unit includes: When the reference detection unit is operating in the temperature monitoring mode, no heating power is applied to each of the reference detection units, the resistance value of each of the reference detection units is detected at this time, and the temperature monitoring data is determined based on the resistance value. When the reference detection unit is operating in the radiation monitoring mode, a reverse bias is applied to each of the reference detection units, and the detection output of the reference detection unit is acquired to determine the radiation monitoring data of the adjacent area.

[0019] In one embodiment, the real-time monitored value includes real-time radiation state parameters; When the monitoring information includes temperature monitoring data, determining the real-time monitoring value corresponding to the array radiation state based on the monitoring information includes: Based on the temperature monitoring data and the preset thermal model, the real-time radiation state parameters corresponding to the micro-emission unit array are determined; the preset thermal model is used to characterize the correspondence between the radiation power and temperature of the micro-emission unit array, and the radiation power is related to the emissivity, radiation area and temperature.

[0020] In one embodiment, the step of correcting the initial drive parameters based on the drive correction parameters to obtain the target drive parameters for each transmitting unit includes: The initial drive parameters of each of the transmitting units are corrected as a whole based on the drive correction parameters; the drive correction parameters are obtained by processing the deviation using a proportional-integral-derivative controller; By combining the individualized calibration data corresponding to each of the aforementioned launch units, the overall corrected drive parameters are corrected by unit-by-unit nonlinear mapping to obtain the target drive parameters of each of the aforementioned launch units.

[0021] In one embodiment, the method further includes: Detecting abnormal cells in the micro-emission unit array; If an abnormal unit is detected, the driving parameters of the transmitting units within a preset range around the abnormal unit are compensated and adjusted based on the driving parameters of at least one neighboring transmitting unit around the abnormal unit, so as to perform spatial interpolation compensation for the area where the abnormal unit is located.

[0022] In one embodiment, the method further includes: When the target equivalent blackbody temperature changes, the storage unit is queried based on the target equivalent blackbody temperature to obtain the updated initial driving parameters, and the updated initial driving parameters are used as feedforward control quantities to drive the micro-emission unit array to quickly approach the target radiation state. During the output radiation process, a driving correction parameter is determined based on the deviation between the real-time monitoring value and the target monitoring value, and the driving correction parameter is used as a feedback control quantity to dynamically adjust the micro-emission unit array.

[0023] Thirdly, this application proposes a semiconductor calibration apparatus, the apparatus comprising: The on-chip integrated infrared radiation source as described in any one of the first aspects is used to output infrared radiation corresponding to the target equivalent blackbody temperature by employing the control method of the infrared radiation source as described in any one of the second aspects. An optical interface is used to align the infrared radiation output from the on-chip integrated infrared radiation source with the receiving optical path of the infrared temperature measuring device under test. The control host is communicatively connected to both the on-chip integrated infrared radiation source and the infrared temperature measuring device under test. It sends a set temperature to the on-chip integrated infrared radiation source to control the on-chip integrated infrared radiation source to output corresponding infrared radiation, and obtains the status feedback of the on-chip integrated infrared radiation source and the measurement results of the infrared temperature measuring device under test. It also calibrates the infrared temperature measuring device under test based on the set temperature, the status feedback, and the measurement results.

[0024] In one embodiment, the device further includes: An external temperature control device is thermally connected to the on-chip integrated infrared radiation source and is used to adjust the operating temperature range of the on-chip integrated infrared radiation source.

[0025] The above-mentioned on-chip integrated infrared radiation source and its control method, as well as the semiconductor calibration device, have at least the following advantages: This application achieves chip-level miniaturization by forming a back-released suspended film region on a semiconductor substrate and integrating a micro-emitter array and a reference detector unit employing a metal-dielectric-metal Fabry-Perot resonant cavity structure on the suspended film region. This enables each emitter unit to self-heat and radiate under electrical drive. The reference detector unit monitors the temperature and / or radiation state of the micro-emitter array in real time. Combined with peripheral circuits electrically connected to the micro-emitter array and reference detector unit, drive control is performed using a row-column interleaved addressing method, and adjustments are made based on initial drive parameters pre-stored in the memory cell. This integrated approach significantly reduces the size and thermal inertia of traditional cavity blackbody radiation sources, improves the response speed of radiation output, and reduces power consumption. Furthermore, the resonant cavity structure allows the radiation output to be concentrated in a preset band, improving the matching with the response band of infrared temperature measurement equipment. Moreover, relying on the cooperation of the reference detection unit and peripheral circuits, this application can also perform real-time monitoring and closed-loop adjustment of the array output, improving the stability, consistency, and repeatability of the radiation output. This facilitates the application of this radiation source as a traceable standard radiation source for high-precision calibration of infrared temperature measurement probes in semiconductor process equipment and makes it easy to integrate into production line testing systems. Attached Figure Description

[0026] Figure 1 This is a block diagram of an on-chip integrated infrared radiation source in one embodiment; Figure 2 This is a schematic diagram showing the distribution of the micro-emission unit array and the reference detection unit in one embodiment; Figure 3 This is a flowchart illustrating a method for controlling an infrared radiation source in one embodiment; Figure 4 This is a structural block diagram of a semiconductor calibration device in one embodiment. Detailed Implementation

[0027] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.

[0028] Some exemplary embodiments of this application have been described for illustrative purposes. It should be understood that this application may be implemented in other ways not specifically shown in the accompanying drawings.

[0029] Please see Figure 1In one exemplary embodiment, this application provides an on-chip integrated infrared radiation source, including: a semiconductor substrate, a micro-emission unit array, a reference detection unit, and peripheral circuitry. A semiconductor substrate having a suspended film region formed by back-side release.

[0030] Specifically, the semiconductor substrate serves as the basic support structure for the on-chip integrated infrared radiation source, supporting the micro-emission unit array, reference detection unit, and peripheral circuits, and enabling electrical connections between the various devices. Exemplarily, the semiconductor substrate in this embodiment can be an SOI substrate or a bulk silicon substrate, with an overall chip size of 5mm × 5mm.

[0031] The suspended membrane region is located in the central region of the semiconductor substrate and is used to support the micro-emission unit array and the reference detection unit. Exemplarily, the suspended membrane region in this embodiment has an area of ​​2 mm × 2 mm.

[0032] Optionally, the suspended membrane region is supported on the semiconductor substrate by a cantilever beam to reduce thermal coupling between the micro-emission unit array and the semiconductor substrate.

[0033] Specifically, the suspended membrane region is connected to the surrounding substrate via four cantilever beams, each 100 μm long and 5 μm wide, made of Si3N4 material. Since the suspended membrane region is connected to the surrounding substrate solely through these cantilever beams, heat conduction between the suspended membrane region and the semiconductor substrate is effectively reduced, heat leakage is decreased, and thermal isolation performance is improved. This, in turn, contributes to improving the electrothermal conversion efficiency and infrared radiation response speed of the micro-emission unit.

[0034] The micro-emission unit array is formed on the suspended membrane region and includes multiple arrayed emission units. Each emission unit is an independent infrared radiation source and adopts a metal-dielectric-metal Fabry-Perot resonant cavity structure. The metal-dielectric-metal Fabry-Perot resonant cavity structure includes a bottom metal layer that also serves as a heating resistor, a dielectric spacer layer, and a top metal layer. The thickness of the dielectric spacer layer is configured to enable the corresponding emission unit to resonate in a preset wavelength band.

[0035] Specifically, the micro-emission unit array is formed on the suspended membrane region. Exemplarily, in this embodiment, the micro-emission unit array consists of 64×64 emission units arranged in an array, each emission unit being independently configured and serving as an independent infrared radiation source. Further, each emission unit has a planar dimension of 25μm×25μm, and the center-to-center distance between adjacent emission units is 30μm. The entire micro-emission unit array is arranged within a suspended membrane region of 2mm×2mm, thereby forming a radiation surface covering the entire suspended membrane region.

[0036] Furthermore, the hierarchical structure of the on-chip integrated infrared radiation source in this embodiment includes, from bottom to top: The substrate is a 500μm thick silicon layer, and a cavity is formed on the back side by deep reactive ion etching (DRIE) to release the suspended film area on the front side.

[0037] The buried oxide layer is a 1μm thick SiO2 layer. When using an SOI substrate, it serves as the substrate's built-in buried oxide layer and as a stop layer for back-side etching.

[0038] The device layer is a 10μm thick silicon layer used to fabricate the support structure.

[0039] The dielectric layer, a 0.5 μm thick Si3N4 layer, is used to achieve electrical isolation and stress buffering. The bottom reflective layer is a 200nm thick Au layer, formed by depositing a 20nm thick Ti adhesion layer. This bottom reflective layer also serves as part of the heating electrode.

[0040] The dielectric spacer layer is a Si3N4 layer, and its thickness is designed according to the target resonant wavelength.

[0041] The top reflective layer, a 15nm thick Au layer, is a semi-transparent metal film used to form the resonant cavity and serve as another electrode.

[0042] The passivation layer, a 200nm thick SiO2 layer, is used to protect the metal layer and adjust its optical properties.

[0043] The transmitting unit employs a metal-dielectric-metal (MIM) Fabry-Perot resonator structure. In this structure, a bottom reflective layer, a dielectric spacer layer, and a top reflective layer together constitute the MIM Fabry-Perot resonator structure. The bottom reflective layer forms the bottom metal layer, which, in addition to providing reflection, also functions as a heating resistor; the top reflective layer forms the top metal layer. For example, the bottom metal layer is a 200 nm thick Au thin film with a reflectivity greater than 98% and a resistivity of approximately 2.2 × 10⁻⁶. -8 Ω·m.

[0044] Optionally, the bottom metal layer is patterned into a meandering shape to increase the resistance and achieve electrothermal conversion. Using the above scheme, the bottom metal layer is designed as a meandering metal strip, which increases the conductive path length and improves the resistance, thereby generating Joule heating when energized, causing the corresponding emitting unit to self-heat and output infrared radiation. Furthermore, a dielectric spacer layer is disposed between the bottom metal layer and the top metal layer to determine the equivalent optical thickness of the resonant cavity, enabling the corresponding transmitting unit to resonate in a preset wavelength band. For example, the preset wavelength band range is 8–14 μm, and the dielectric spacer layer is made of Si3N4 material, whose refractive index is approximately 2.0 in the 8–14 μm band. According to the Fabry-Perot resonance condition: 2ndcosθ + φ = mλ; where n is the refractive index of the dielectric layer, d is the thickness of the dielectric layer, θ is the incident angle, φ is the phase shift introduced by the metal mirror, m is the resonance order, and λ is the wavelength. In this embodiment, θ = 0° and m = 1 are taken. Taking the design center wavelength λ0 = 10 μm for a single transmitting unit as an example, when n ≈ 2.0, the thickness d of the dielectric spacer layer can be configured as: d = λ0 / (2n) = 10 / (2×2) = 2.5 μm. In this embodiment, the dielectric spacer layer can be a Si3N4 layer with a thickness of 2.5±0.01μm, so that the corresponding emission unit can resonate within a preset band (8~14μm) and form an emission peak near about 10μm, with a full width at half maximum (FWHM) of about 1~2μm.

[0045] Optionally, the top metal layer is a semi-transparent metal film used to achieve infrared radiation emission and optical field oscillation within the resonant cavity. For example, the top metal layer is a 15nm thick Au semi-transparent metal film with a transmittance of approximately 10%–20% and a reflectance of approximately 80%. Electrodes are led out from the bottom and top metal layers of each emitting unit and connected to the row and column lines respectively, thereby enabling cross-point addressing and allowing the peripheral circuitry to independently drive and control each emitting unit.

[0046] Furthermore, in order to obtain a wider spectral coverage in the 8–14 μm band, in some embodiments, this application can also make multiple emitting units form different resonant peak wavelengths by slightly different thicknesses of the dielectric spacer layer between different emitting units, thereby achieving quasi-continuous spectrum coverage by superimposing multiple resonant peaks.

[0047] The reference detection unit, formed on the suspended membrane region, is used to acquire monitoring information of the micro-emission unit array, including temperature status and / or radiation status.

[0048] Optionally, the reference detection unit and the transmitting unit have the same layer structure.

[0049] Specifically, the reference detection unit also adopts a metal-dielectric-metal Fabry-Perot resonator structure, including a bottom metal layer, a dielectric spacer layer, and a top metal layer. By using the same layer structure as the transmitting unit, the reference detection unit and the transmitting unit can maintain a high degree of consistency in thermal characteristics, optical characteristics, and structural stress characteristics, thereby improving the accuracy of monitoring information.

[0050] Optionally, there are multiple reference detection units, each of which is located in the peripheral region and the central region of the micro-emission unit array.

[0051] Please see Figure 2 , Figure 2 The diagram shows the distribution of the micro-emission unit array and the reference detection unit. Figure 2 The micro-emission unit array shown is a 64×64 array, that is Figure 2 The grid area in the image represents 4096 emission units. Figure 2 The number of reference detection elements is six, of which four are reference detection elements ( Figure 2 R1-R4 shown in the diagram are respectively located in the four corner regions of the micro-emission unit array, and two reference detection units ( Figure 2 R5 and R6 (shown in the diagram) are positioned near the center of the micro-emission unit array. This distribution method allows for monitoring not only the temperature and / or radiation states of the edge and corner regions of the micro-emission unit array, but also the temperature and / or radiation states of the central region of the array, thereby obtaining overall distribution information of the micro-emission unit array on the suspended membrane region. Optionally, the reference detection unit in this embodiment can operate in either a temperature monitoring mode or a radiation monitoring mode. In temperature monitoring mode, no heating power is applied or only a very small bias is applied to obtain the temperature state at the corresponding location by detecting its electrical parameters. In radiation monitoring mode, its detection output can characterize the radiation state of the corresponding region. Thus, the reference detection unit can provide array-level monitoring information to the peripheral circuitry, providing a precise basis for subsequent drive correction, uniformity compensation, and closed-loop control of the micro-emission unit array.

[0052] The peripheral circuit is electrically connected to the micro-emitting unit array and the reference detection unit, respectively. It is used to process the output of the reference detection unit and drive the micro-emitting unit array according to the row and column interleaving addressing method. The peripheral circuit includes a storage unit, which is used to store the initial driving parameters of each transmitting unit.

[0053] Specifically, in addition to the storage units, the peripheral circuitry includes functional modules such as row decoders, column decoders, digital-to-analog converters (DACs), analog-to-digital converters (ADCs), power drive arrays, and controllers. The row and column decoders are used to select the target transmitting unit in the micro-emitting unit array using a row-column interleaving addressing method; the DAC generates corresponding analog drive signals based on control commands; the power drive array applies drive voltage or drive current to the selected transmitting unit, causing Joule heating in the bottom metal layer of the corresponding transmitting unit, thereby outputting infrared radiation; the ADC performs analog-to-digital conversion on the analog monitoring signal output by the reference detection unit; and the controller processes the output signal of the reference detection unit and adjusts the drive parameters of the micro-emitting unit array based on the processing results.

[0054] For example, in actual operation, the temperature and / or radiation status signals output by the reference detection unit are first signal-conditioned and then input to the ADC. The controller then analyzes and processes the digitized monitoring signals to obtain the monitoring information corresponding to the micro-emission unit array. The controller compares the monitoring information with the target state to obtain the corresponding drive correction amount, and combines it with the initial drive parameters of each emission unit pre-stored in the storage unit to generate the corresponding drive control command. Subsequently, the DAC and power drive array output the corresponding drive signal to the micro-emission unit array according to the drive control command, thereby realizing the row and column interleaved addressing drive control of each emission unit.

[0055] Optionally, the initial driving parameters can be at least one of the driving voltage, driving current, and pulse width modulation duty cycle corresponding to each transmitting unit at a preset target temperature. Furthermore, the initial driving parameters can be obtained through pre-calibration and stored in a table in a storage unit, allowing for quick lookup of the initial driving parameters for each transmitting unit based on the target equivalent blackbody temperature during operation. In this way, even with individual differences in the micro-emitting unit array, this application can still provide suitable initial driving conditions for each transmitting unit, thereby improving the consistency and stability of the overall radiation output.

[0056] Optionally, the controller in this embodiment can be a PID controller or a digital control module containing a PID control algorithm. By performing a closed-loop comparison between the real-time output of the reference detection unit and the target output, the controller can dynamically adjust the driving parameters of the micro-emission unit array, thereby improving the output accuracy, response speed, and stability of the on-chip integrated infrared radiation source.

[0057] Optionally, some functional modules in the peripheral circuitry can be integrated into an on-chip structure formed on a semiconductor substrate, while others can be located outside the on-chip structure. For example, row decoders, column decoders, and some signal conditioning circuits can be integrated on the on-chip structure to improve integration and shorten signal transmission paths; while at least some of the ADC, DAC, controller, and memory units can be externally located as needed to reduce chip manufacturing complexity and improve system design flexibility.

[0058] The aforementioned on-chip integrated infrared radiation source integrates a micro-emitting unit array and a reference detector unit by forming a suspended film region on a semiconductor substrate. Each emitting unit can self-heat and output infrared radiation under electrical drive. Simultaneously, the reference detector unit acquires the temperature and / or radiation status of the micro-emitting unit array, and peripheral circuitry processes the output of the reference detector unit and drives the micro-emitting unit array. Therefore, this application not only achieves chip-level miniaturization, reducing the problems of large size and high thermal inertia of traditional cavity blackbody radiation sources, but also achieves fast response and low-power output through the micro-emitting unit array. Furthermore, by utilizing a metal-dielectric-metal Fabry-Perot resonant cavity structure, the emitting units can resonate in a preset wavelength band, thereby improving the matching between the radiation output and the target infrared temperature measurement band. Moreover, through the cooperation of the reference detector unit and peripheral circuitry, the stability, consistency, and repeatability of the array output can be improved, thus facilitating its application as a standard radiation source in infrared temperature measurement equipment, especially for high-precision calibration of infrared temperature probes in semiconductor process equipment. Please see Figure 3 In one exemplary embodiment, this application provides a control method for an infrared radiation source, applicable to the on-chip integrated infrared radiation source provided in the above embodiments. The control method specifically includes the following steps: Step 302: Obtain the target equivalent blackbody temperature and its corresponding target monitoring value. Specifically, the target equivalent blackbody temperature refers to the pre-set equivalent blackbody radiation temperature expected to be output by the on-chip integrated infrared radiation source, used to characterize the target radiation output state. For example, the target equivalent blackbody temperature is any target temperature point within the range of -50℃ to 200℃.

[0059] The target monitoring value refers to the target reference quantity corresponding to the target equivalent blackbody temperature, used for comparison in subsequent closed-loop control. Specifically, in this embodiment, the target reference quantity is the target state parameter that the reference detection unit and / or micro-emission unit array should present when the on-chip integrated infrared radiation source reaches the target equivalent blackbody temperature. This target state parameter can be at least one of the following: temperature monitoring value, radiation monitoring value, and real-time radiation state parameter.

[0060] Step 304: Based on the target equivalent blackbody temperature, query the storage unit to obtain the initial driving parameters corresponding to each transmitting unit. Specifically, the storage unit pre-stores the initial driving parameter information corresponding to each transmitting unit. These initial driving parameters are predetermined driving parameters for the corresponding transmitting unit to output corresponding infrared radiation at a given target equivalent blackbody temperature. The initial driving parameters include at least one of driving voltage, driving current, and pulse width modulation duty cycle. Because different transmitting units may have individual differences during manufacturing, the initial driving parameters for each transmitting unit can be the same or different. Step 306: Based on the initial driving parameters, generate row and column gating signals and pulse width modulation signals for controlling the micro-emitting unit array, so that each emitting unit self-heats and outputs infrared radiation. Specifically, the row and column gating signals are used to determine the gating order and position of each transmitter unit in the micro-transmitter array, and the pulse width modulation signal is used to characterize the driving intensity applied to the corresponding transmitter unit. The row and column addresses corresponding to each transmitter unit can be determined based on their positional relationship in the micro-transmitter array. Then, according to a preset row-column interleaving addressing method, based on the initial driving parameters corresponding to each transmitter unit, row and column gating signals are generated to sequentially select the corresponding row and column lines, and pulse width modulation signals corresponding to each transmitter unit are generated.

[0061] Step 308: Obtain the monitoring information of the reference detection unit, and determine the real-time monitoring value corresponding to the array radiation state based on the monitoring information.

[0062] Specifically, the monitoring information includes temperature status information and / or radiation status information. Real-time monitoring values ​​refer to parameters characterizing the actual radiation status of the micro-emission unit array at the current moment. These real-time monitoring values ​​can serve as the basis for subsequent comparisons with target monitoring values ​​to reflect the degree of deviation of the current array radiation output from the target radiation output. Optionally, real-time monitoring values ​​can be temperature monitoring values, radiation monitoring values, and / or radiation status parameters determined based on the monitoring information.

[0063] Step 310: Determine the drive correction parameters based on the deviation between the real-time monitoring value and the target monitoring value; correct the initial drive parameters based on the drive correction parameters to obtain the target drive parameters for each transmitting unit.

[0064] Specifically, the drive correction parameter is used to characterize the amount of adjustment to compensate for the current output deviation, while the target drive parameter refers to the drive parameter obtained after correction based on the initial drive parameter.

[0065] Step 312: Perform closed-loop drive control on the micro-emission unit array according to the target driving parameters to output infrared radiation corresponding to the target's equivalent blackbody temperature.

[0066] Specifically, in the closed-loop drive control process, the micro-emission unit array is driven and controlled based on the target drive parameters corresponding to each transmission unit in order to adjust the actual working state of each transmission unit so that the overall radiation output of the micro-emission unit array gradually approaches the target radiation output state.

[0067] The aforementioned on-chip integrated infrared radiation source and its control method, by forming a back-released suspended film region on a semiconductor substrate, and integrating a micro-emitting unit array and a reference detector unit employing a metal-dielectric-metal Fabry-Perot resonant cavity structure on the suspended film region, enables each emitting unit to self-heat and radiate under electrical drive. The reference detector unit is used to monitor the temperature and / or radiation state of the micro-emitting unit array in real time. Combined with peripheral circuits electrically connected to the micro-emitting unit array and the reference detector unit, drive control is performed according to a row-column interleaved addressing method, and adjustments are made based on initial drive parameters pre-stored in the memory unit. Therefore, this application not only enables… This invention achieves chip-level miniaturization and integration, significantly reducing the volume and thermal inertia of traditional cavity blackbody radiation sources, improving the response speed of radiation output and reducing power consumption. Moreover, the resonant cavity structure can concentrate the radiation output to a preset band, improving the matching with the response band of infrared temperature measurement equipment. Furthermore, relying on the cooperation of the reference detection unit and peripheral circuits, this application can also perform real-time monitoring and closed-loop adjustment of the array output, improving the stability, consistency and repeatability of the radiation output. This facilitates the application of this radiation source as a traceable standard radiation source for high-precision calibration of infrared temperature measurement probes in semiconductor process equipment, and makes it easy to integrate into production line testing systems.

[0068] Optionally, based on the target equivalent blackbody temperature, the initial driving parameters corresponding to each transmitting unit are obtained by querying the storage unit, including: Individual calibration data for each transmitting unit can be retrieved from the storage unit; the individual calibration data includes at least one of the following: the correspondence between driving parameters and radiation intensity, the correspondence between driving parameters and equivalent radiation temperature, and the correspondence between resistance value and temperature; Based on the target equivalent blackbody temperature, interpolation is performed on the individualized calibration data corresponding to each transmitting unit to obtain the initial driving parameters corresponding to each transmitting unit. The initial driving parameters include at least one of driving voltage, driving current, and pulse width modulation duty cycle.

[0069] Optionally, individualized calibration data is constructed during the pre-calibration phase, and the construction methods include: Within a preset temperature range, a traceable blackbody is used as a reference to calibrate each transmitting unit point by point; the correspondence between the driving parameters and the equivalent radiation temperature of each transmitting unit at multiple calibration temperature points is recorded; based on the correspondence, individualized calibration data for each transmitting unit is constructed and written into the storage unit.

[0070] Specifically, during the pre-calibration stage, each emitting unit is calibrated across its entire temperature range. For example, the calibration temperature range can be -50℃ to 200℃, with a calibration step size of 10℃. At each calibration temperature point, an externally traceable blackbody is used as a reference radiation source to calibrate each emitting unit in the micro-emitting unit array. Due to process variations, the resistance, resonant wavelength, and radiation efficiency of different emitting units may have slight differences. Therefore, this application records at least one of the following correspondences for each emitting unit at different calibration temperature points: the relationship between driving parameters and radiation intensity, the relationship between driving parameters and equivalent radiation temperature, and the relationship between resistance and temperature, to form individualized calibration data for each emitting unit. Based on these correspondences, one or more calibration curves can be generated for each emitting unit to reflect its radiation output characteristics under different driving conditions.

[0071] Furthermore, during the operation phase, based on the obtained target equivalent blackbody temperature query storage unit, since the target equivalent blackbody temperature may not exactly correspond to a certain calibration temperature point, this application performs linear interpolation on the calibration data corresponding to two adjacent calibration temperature points of the target equivalent blackbody temperature, thereby obtaining the initial driving parameters of the corresponding transmitting unit at the target equivalent blackbody temperature.

[0072] Furthermore, in some embodiments, the theoretically achievable target radiation intensity of each transmitting unit in the array can be calculated first based on the target equivalent blackbody temperature. Then, based on the individualized calibration data corresponding to each transmitting unit, the initial pulse width modulation duty cycle required to achieve the target radiation intensity can be calculated by querying or interpolation. Thus, this application can provide each transmitting unit with an initial driving basis adapted to the target equivalent blackbody temperature before the start of driving control, thereby providing a parameter basis for the subsequent generation of row and column gating signals and pulse width modulation signals.

[0073] By adopting the above scheme, this application performs full-temperature-range unit-by-unit calibration on each transmitting unit during the pre-calibration stage and stores the resulting individualized calibration data in the storage unit. This fully considers the differences in resistance, resonant wavelength, and radiation efficiency between different transmitting units due to process fluctuations. Thus, during operation, the initial driving parameters corresponding to each transmitting unit can be quickly queried and interpolated based on the target equivalent blackbody temperature. This improves the matching degree between the initial driving parameters and the actual target radiation state, reduces the amount of subsequent closed-loop adjustment, and improves the response speed.

[0074] Optionally, based on the initial driving parameters, row and column gating signals and pulse width modulation signals for controlling the micro-emitting unit array are generated, including: The micro-emission unit array is scanned according to a preset cycle and a preset sequence; For each selected row and / or column, a corresponding pulse width modulation signal is generated based on the initial driving parameters; The duty cycle of the pulse width modulation signal is determined based on the initial driving parameters in order to control the average heating power of each transmitting unit and adjust the radiation intensity of each transmitting unit.

[0075] Specifically, in this embodiment, the peripheral circuit can scan the micro-emitting unit array using a row-column interleaved addressing method. For example, the micro-emitting unit array is a 64×64 array, comprising 4096 transmitting units, each of which can be addressed independently. A scan period and a row selection order and / or column selection order within a scan period are preset. During control, the row and column addresses corresponding to each transmitting unit are first determined based on their positional relationship within the array; then, according to the preset period and preset order, the corresponding row lines and / or column lines are sequentially selected, thereby achieving row-by-row scanning, column-by-column scanning, or a combination of row-by-row and column-by-column scanning of the micro-emitting unit array.

[0076] In one example, the frame period for each frame can be set to 1ms, and each transmitting unit can be selected once per frame. During the selection period, a constant voltage can be applied to the corresponding transmitting unit, and its effective conduction time can be adjusted by pulse width modulation. That is, when each row and / or column is selected, a pulse width modulation signal is generated for the target transmitting unit in that row and / or column based on its corresponding initial driving parameters. If the initial driving parameters include duty cycle information, the corresponding pulse width modulation signal can be generated directly based on the duty cycle; if the initial driving parameters include driving voltage and / or driving current, the corresponding duty cycle can be determined according to a preset conversion relationship, and the corresponding pulse width modulation signal can be further generated.

[0077] The duty cycle of the pulse width modulation signal characterizes the proportion of effective driving time within a modulation cycle. Generally, a transmitting unit with a larger duty cycle has a relatively higher average heating power and correspondingly higher radiation intensity; a transmitting unit with a smaller duty cycle has a relatively lower average heating power and correspondingly lower radiation intensity. By setting different duty cycles for different transmitting units, the average heating power applied to each transmitting unit can be controlled, thereby adjusting the self-heating degree and radiation intensity of each transmitting unit.

[0078] Furthermore, in this embodiment, the thermal time constant of the transmitting unit is approximately 50 μs. Since the frame period matches the thermal response characteristics of the transmitting unit, the temperature change of each transmitting unit under continuous frame driving conditions can exhibit a smooth change. That is, although the driving method of this application adopts frame-by-frame gating and pulse width modulation, since the average heating power is controlled by the duty cycle and the unit thermal response speed is relatively fast, the temperature adjustment of each transmitting unit can be regarded as a continuous adjustment process. Thus, the temperature of the transmitting unit and the corresponding radiation intensity can be continuously adjusted, which is beneficial for achieving precise setting and stable output of the target equivalent blackbody temperature.

[0079] By adopting the above scheme, this application employs a row-column interleaved addressing method to achieve orderly driving and independent adjustment of each emitting unit in the array. This effectively improves the array driving efficiency while ensuring the flexibility of drive control and the fine adjustment of radiation intensity. Simultaneously, by applying a constant voltage during the gating period and controlling the average heating power using the duty cycle of the pulse width modulation signal, the temperature and radiation intensity of each emitting unit can be continuously adjusted. This is beneficial for improving the adjustment resolution, response smoothness, and control accuracy of the on-chip integrated infrared radiation source output.

[0080] Optionally, when the monitoring information includes temperature monitoring data and radiation monitoring data, and the reference detection unit is operating in temperature monitoring mode or radiation monitoring mode, the monitoring information of the reference detection unit is acquired, including: When the reference detection unit is working in temperature monitoring mode, no heating power is applied to each reference detection unit. The resistance value of each reference detection unit is detected at this time, and the temperature monitoring data is determined based on the resistance value. When the reference detection unit is operating in radiation monitoring mode, a reverse bias is applied to each reference detection unit, and the detection output of the reference detection unit is acquired to determine the radiation monitoring data of the adjacent area.

[0081] Specifically, when the reference detection units operate in temperature monitoring mode, no driving power for heating is applied to each reference detection unit, or only a very small bias is applied, allowing them to function as resistance temperature sensors. The resistance value of each reference detection unit in this state is detected, and the temperature monitoring data for the corresponding location is determined based on the resistance value. Optionally, in this embodiment, the resistance value is measured using a four-wire method to reduce the influence of lead resistance and contact resistance on the measurement results. Since the reference detection units are distributed at the center and four corners of the array, temperature state information for the corresponding areas can be obtained to characterize the temperature distribution of the micro-emission unit array on the suspended membrane region. Furthermore, if the suspended membrane thermal conductivity design minimizes temperature differences at each location, the temperature monitoring data corresponding to the reference detection units in the central region can also be used as a representation of the array's average temperature.

[0082] Furthermore, when the reference detection units operate in radiation monitoring mode, a reverse bias can be applied to each reference detection unit to make it operate in photovoltaic mode and / or photoconductive mode, thereby using it as an infrared detector. The radiation monitoring data is used to characterize the radiation intensity state of the emitting unit region adjacent to the reference detection unit. In some embodiments, considering that the reference detection unit itself is formed on the suspended membrane region, directly using its detection output to characterize the radiation state may introduce certain errors. Therefore, the radiation monitoring mode can be used as an auxiliary monitoring method, the temperature monitoring mode as the primary monitoring method, and a preset thermal model can be further combined to calculate the array radiation output.

[0083] By employing the above implementation method, and by operating the reference detection unit in either temperature monitoring mode or radiation monitoring mode, the operating status information of the micro-emission unit array can be obtained from different angles. This improves the flexibility and completeness of the status monitoring of the micro-emission unit array, which is beneficial for more accurately determining the real-time monitoring values ​​during subsequent closed-loop drive control, and enhances the stability, consistency, and repeatability of infrared radiation output.

[0084] Optionally, when the real-time monitored values ​​include real-time radiation state parameters and the monitoring information includes temperature monitoring data, the real-time monitored values ​​corresponding to the array radiation state are determined based on the monitoring information, including: Based on temperature monitoring data and a preset thermal model, the real-time radiation state parameters corresponding to the micro-emission unit array are determined. The preset thermal model is used to characterize the relationship between the radiation power and temperature of the micro-emission unit array. The radiation power is related to the emissivity, radiation area, and temperature.

[0085] Specifically, since the reference detection unit and the emission unit are formed on the same suspended membrane region and have the same layer structure, the temperature monitoring data of the reference detection unit can be used to characterize the temperature state of the emission unit in the corresponding region, and further combined with the preset thermal model to calculate the real-time radiation state parameters of the micro emission unit array.

[0086] For example, the radiated power of a single transmitting unit With temperature The relationship can be represented as:

[0087] in, For emissivity; It is the Stefan-Boltzmann constant; Here, represents the radiating area of ​​the transmitting unit. In this embodiment, the emissivity can be determined by the resonant cavity structure of the transmitting unit, for example, it can be taken as 0.8; the area of ​​the transmitting unit can be determined by the unit size, for example, when the unit size is 25μm×25μm, the unit area is approximately 6.25×10 -¹ 0 m². Therefore, based on the temperature monitoring data measured by the reference detection unit and combined with the preset thermal model, the radiated power of the corresponding regional emitting unit can be calculated.

[0088] Furthermore, after obtaining the radiated power, the real-time radiation state parameters corresponding to the current radiation output are determined by combining the blackbody radiation conversion relationship. Optionally, the real-time radiation state parameters can be at least one of real-time radiated power, real-time radiated intensity, and real-time equivalent blackbody temperature.

[0089] In some embodiments, since the transmitting unit is in an actively heated state while the reference detection unit does not apply heating power in temperature monitoring mode, the actual temperature of the transmitting unit may be slightly higher than that of the adjacent reference detection unit. To address this, a temperature difference correction term can be introduced into the aforementioned preset thermal model to improve the accuracy of the calculated real-time radiation state parameters.

[0090] By employing the above-described implementation method, and by acquiring temperature monitoring data from the reference detection unit and combining it with a preset thermal model to determine the real-time radiation state parameters corresponding to the micro-emission unit array, the temperature information acquired by the reference detection unit can be further converted into parameters characterizing the actual radiation output state, thereby providing a more direct feedback basis for subsequent closed-loop control. Furthermore, since the preset thermal model correlates radiation power with emissivity, radiation area, and temperature, this application can achieve real-time calculation of the array's radiation state without directly relying on an external radiation detector, which is beneficial for improving the system's miniaturization and integration.

[0091] Optionally, the initial drive parameters are corrected based on the drive correction parameters to obtain the target drive parameters for each transmitting unit, including: The initial drive parameters of each transmitter unit are corrected as a whole based on the drive correction parameters. The drive correction parameters are obtained by processing the deviation using a proportional-integral-derivative controller. Combined with the individualized calibration data corresponding to each transmitter unit, the overall corrected drive parameters are corrected by nonlinear mapping unit by unit to obtain the target drive parameters of each transmitter unit.

[0092] Specifically, the target monitoring value can be a corresponding temperature parameter calculated from the target's equivalent blackbody temperature, or a target state parameter corresponding to the target's equivalent blackbody temperature. For example, in the embodiments of this application, the target monitoring value can be temperature data, and the reference detection unit can monitor the array temperature corresponding to the micro-emission unit array in real time to obtain the real-time monitoring temperature. During the control process, the target temperature will be monitored in real time, corresponding to the target equivalent blackbody temperature. By comparing the two, the temperature difference between them can be obtained. .

[0093] In this embodiment, the suspended thermal system housing the micro-emission unit array can be approximated as a first-order inertial element with a time constant of approximately 50 μs. Based on this thermal response characteristic, a proportional-integral-derivative controller can be used to control temperature deviations. The data is processed to obtain drive correction parameters for correcting the drive state. For example, the sampling frequency of the control system can be set to 10 kHz to periodically sample the output of the reference probe unit during array drive. The parameters of the proportional-integral-derivative controller can be preset using a tuning method, such as the Ziegler-Nichols method, to ensure small overshoot and high steady-state accuracy during the temperature regulation process of the micro-emitter array in control operations.

[0094] After obtaining the drive correction parameters, this application uses the drive correction parameters as a uniform correction amount across the entire array to synchronously adjust the initial drive parameters corresponding to each transmitting unit, thereby obtaining the overall corrected drive parameters. For example, when the initial drive parameters are the pulse width modulation duty cycles corresponding to each transmitting unit, the duty cycles of the entire array can be corrected using the drive correction parameters; when the initial drive parameters are the drive voltage and / or drive current, the corresponding drive voltage and / or drive current can also be corrected based on the drive correction parameters.

[0095] Furthermore, considering the potential individual differences in resistance, resonant wavelength, and radiation efficiency among the various transmitting units during manufacturing, after the overall correction is completed, the driving parameters can be further corrected using unit-by-unit nonlinear mapping, based on the individualized calibration data corresponding to each transmitting unit. For example, for transmitting units with high resistance, the corresponding pulse width modulation duty cycle can be further increased based on the overall correction; for transmitting units with high or low radiation efficiency, their driving parameters can be specifically corrected based on their individualized calibration data. Through the aforementioned unit-by-unit nonlinear mapping correction, the final target driving parameters for each transmitting unit can be obtained. These target driving parameters can be further used to generate the final row and column gating signals and pulse width modulation waveforms to achieve closed-loop drive control of the micro-transmitter array. Therefore, this application can both rapidly correct the overall output state of the array using a proportional-integral-derivative controller and compensate for local unit differences by combining unit-by-unit individualized calibration data, thereby improving the accuracy and consistency of the overall array output.

[0096] By employing the above implementation method, a proportional-integral-differential controller is used to process the deviation between the real-time monitoring results acquired by the reference detection unit and the target monitoring value, obtaining driving correction parameters for correcting the driving state, thereby achieving rapid feedback adjustment of the overall output state of the micro-emission unit array. Simultaneously, based on the overall correction, this application further combines individual calibration data corresponding to each emission unit for unit-by-unit nonlinear mapping correction, which can also compensate for individual deviations caused by differences in resistance, resonant wavelength, and radiation efficiency between different emission units. Therefore, this application not only improves the overall temperature and radiation output response speed of the micro-emission unit array, but also improves the array output consistency, spatial uniformity, and control accuracy, thus facilitating the high-precision and stable output of the target's equivalent blackbody temperature by an on-chip integrated infrared radiation source.

[0097] Optionally, the above-mentioned method for controlling the infrared radiation source further includes: Detect abnormal units in the micro-emission unit array; when an abnormal unit is detected, compensate and adjust the driving parameters of the transmission units within a preset range around the abnormal unit based on the driving parameters of at least one neighboring transmission unit around the abnormal unit, so as to perform spatial interpolation compensation for the area where the abnormal unit is located.

[0098] Specifically, during operation, this application combines the monitoring information of the reference detection unit, the real-time driving status of each transmitting unit, and pre-stored individualized calibration data to perform status detection on each transmitting unit in the micro-transmitting unit array. Optionally, when a transmitting unit has abnormal output, radiation intensity significantly lower than the target value, or fails to achieve the target driving effect due to manufacturing defects, aging failure, or other reasons, the transmitting unit can be identified as an abnormal unit.

[0099] After detecting an abnormal unit, the compensation region surrounding the abnormal unit is further determined, and the driving parameters corresponding to the current transmitting units within the compensation region are obtained. The current driving parameters are then adjusted for compensation. Optionally, when the driving parameter is a pulse width modulation duty cycle, the duty cycle of neighboring transmitting units within a preset range around the abnormal unit can be increased by a preset ratio, thereby increasing the average heating power and radiation intensity of the neighboring transmitting units accordingly, thus providing coordinated compensation for the missing radiation output of the abnormal unit.

[0100] Furthermore, in some embodiments, the compensation weight corresponding to each neighboring transmitting unit can be determined based on the actual state of multiple neighboring transmitting units surrounding the anomalous unit, and the driving parameters of each neighboring transmitting unit can be adjusted accordingly. The actual state of each neighboring transmitting unit includes its current location, radiation capability, individualized calibration data, and current driving margin. Using this scheme, neighboring transmitting units closer to the anomalous unit and with stronger radiation compensation capabilities can have relatively larger driving parameter adjustments; neighboring transmitting units farther from the anomalous unit or with smaller current driving margins can have relatively smaller driving parameter adjustments. This achieves spatial interpolation compensation for the region where the anomalous unit is located.

[0101] By adopting the above implementation method, when an abnormal unit is detected in the micro-emission unit array, by compensating and adjusting the driving parameters of the emission units within a preset range around the abnormal unit, spatial interpolation compensation can be performed on the area where the abnormal unit is located using the neighboring emission units, thereby reducing the local defect impact of the abnormal unit on the overall radiation field distribution, and thus maintaining the continuity and uniformity of the overall radiation output of the array through collaborative compensation.

[0102] Optionally, the above-mentioned method for controlling the infrared radiation source further includes: When the target equivalent blackbody temperature changes, the storage unit is queried based on the target equivalent blackbody temperature to obtain the updated initial driving parameters. The updated initial driving parameters are then used as feedforward control quantities to drive the micro-emission unit array to quickly approach the target radiation state. During the output radiation process, the driving correction parameters are determined based on the deviation between the real-time monitoring value and the target monitoring value. The driving correction parameters are then used as feedback control quantities to dynamically adjust the micro-emission unit array.

[0103] Specifically, when the target equivalent blackbody temperature changes, it is necessary to re-query the updated initial driving parameters corresponding to each emission unit in the storage unit based on the changed target equivalent blackbody temperature. The updated initial driving parameters can be used as feedforward control quantities to directly determine the initial driving state of the micro-emission unit array in the early stage of target temperature switching. Using the above scheme, this application can apply the corresponding drive to the micro-emission unit array based on the pre-stored parameters corresponding to the target equivalent blackbody temperature without waiting for error accumulation, thereby enabling the radiation output of the micro-emission unit array to quickly approach the new target radiation state.

[0104] Furthermore, during the infrared radiation output of the micro-emission unit array, the reference detection unit continuously acquires the real-time monitoring values ​​corresponding to the micro-emission unit array and compares them with the target monitoring values ​​to obtain the deviation between the two. Subsequently, the driving correction parameters are determined based on the deviation, and these parameters are used as feedback control quantities to dynamically correct the current driving state of the micro-emission unit array, so that the actual radiation output of the micro-emission unit array gradually approaches the target radiation state. That is, this application adopts a combination of feedforward control and feedback control to achieve driving control of the micro-emission unit array. Among them, feedforward control is used to quickly establish the initial driving conditions corresponding to the new target state based on the pre-stored driving parameters when the target equivalent blackbody temperature changes; feedback control is used to continuously correct the driving parameters based on the deviation between the real-time monitoring results and the target state during the output radiation process, thereby achieving dynamic adjustment.

[0105] Optionally, in the initial stage after the target equivalent blackbody temperature changes, the array can be primarily driven by feedforward control to improve response speed. After the radiation output of the micro-emission unit array gradually approaches the target state, residual deviations can be primarily suppressed by feedback control to improve output stability and control accuracy. This allows the micro-emission unit array to achieve both rapid response and precise stability during temperature switching.

[0106] By employing the above implementation method, when the equivalent blackbody temperature of the target changes, feedforward control is implemented based on the updated initial driving parameters. This allows the micro-emission unit array to be directly provided with driving conditions closer to the target radiation state when the temperature point changes, thereby shortening the system's response time from the original state to the new target state. Simultaneously, feedback control is implemented based on the deviation between the real-time monitoring value and the target monitoring value during the output radiation process. This also enables dynamic adjustment of the array output, reducing residual errors and improving output stability and control accuracy. Thus, it is possible to simultaneously achieve rapid response and high-precision control during the target temperature switching process.

[0107] The above-mentioned control method for infrared radiation sources enables each emitting unit to achieve self-heating radiation output by performing row and column gating and pulse width modulation driving on the micro-emitting unit array. This eliminates the need for the overall constant temperature cavity and long thermal equilibrium process required by traditional cavity blackbodies, thereby significantly reducing thermal inertia and improving response speed. This is beneficial for achieving rapid temperature point switching and millisecond-level dynamic adjustment.

[0108] Furthermore, this application incorporates a metal-dielectric-metal Fabry-Perot resonator structure, enabling the emitting unit to generate radiation output in the 8–14 μm band that matches the response range of infrared thermometry equipment, thereby improving spectral matching.

[0109] Furthermore, by querying the initial driving parameters based on the target equivalent blackbody temperature and controlling the average heating power in combination with the pulse width modulation duty cycle, this application enables the temperature and radiation intensity of each transmitting unit to be continuously adjustable, thereby achieving continuous setting of the target equivalent blackbody temperature.

[0110] Furthermore, this application employs an array-based spatial synthesis method, combined with reference detection unit monitoring, drive correction, and spatial interpolation compensation of anomalous units, which can actively compensate for the overall radiation field of the array, thereby improving the stability, consistency, and repeatability of the radiation output.

[0111] In summary, this application not only achieves rapid response, full-band matching, and continuous temperature adjustment, but also enables active compensation through a synthetic array. This is beneficial for its application as a standard radiation source in infrared temperature measurement equipment, especially for high-precision calibration of infrared temperature probes in semiconductor process equipment. It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0112] Please see Figure 4 In one exemplary embodiment, this application provides a semiconductor calibration device, including: an on-chip integrated infrared radiation source provided in the above embodiments, used to output infrared radiation corresponding to the target equivalent blackbody temperature using the control method of the infrared radiation source provided in the above embodiments.

[0113] An optical interface is used to align the infrared radiation output from the on-chip integrated infrared radiation source with the receiving optical path of the infrared temperature measuring device under test.

[0114] The control host is communicatively connected to both the on-chip integrated infrared radiation source and the infrared temperature measuring device under test. It sends a set temperature to the on-chip integrated infrared radiation source to control the output of corresponding infrared radiation, and obtains the status feedback of the on-chip integrated infrared radiation source and the measurement results of the infrared temperature measuring device under test. Based on the set temperature, status feedback and measurement results, it calibrates the infrared temperature measuring device under test.

[0115] Optionally, the semiconductor calibration device also includes: An external temperature control device is thermally connected to the on-chip integrated infrared radiation source to adjust the operating temperature range of the on-chip integrated infrared radiation source.

[0116] For example, setting an on-chip integrated infrared radiation source to output a target equivalent blackbody temperature corresponding to 100°C includes the following steps: Step 1: After the chip is powered on, it enters the initialization state, at which point it reads the pre-stored individualized calibration data from the storage unit. After initialization, the micro-emission unit array is in standby mode, and each emission unit is not heated.

[0117] Step 2: Receive the target equivalent blackbody temperature setting value written by the engineer. In this embodiment, the target equivalent blackbody temperature is set to T_set=100℃.

[0118] Step 3: Based on the target equivalent blackbody temperature T_set and the pre-stored individualized calibration data in the storage unit, obtain the initial driving parameters corresponding to each transmitting unit. For example, the initial driving parameters are the initial pulse width modulation duty cycle D0(i,j) corresponding to each transmitting unit, so that the micro-emitting unit array theoretically forms a target radiation field corresponding to 100℃.

[0119] Step 4: Start the scan drive of the micro-transmitter array according to the initial drive parameters. Specifically, the row decoder selects rows one by one in a preset order, and the column driver outputs the corresponding PWM waveform according to the initial pulse width modulation duty cycle of each transmitter unit during the selection period of the corresponding row, thereby driving each transmitter unit in that row to heat up. For example, the row period can be 15.6μs, and the total frame period can be 1ms.

[0120] Step 5: During the array scanning process, the reference detection unit monitors the working status of the suspended membrane region in real time. For example, temperature monitoring data can be acquired by reference detection units R5 and R6 located in the center region of the array and converted into digital values ​​via an ADC. Based on the temperature monitoring data and a preset thermal model, the equivalent radiation temperature T_rad corresponding to the current array is calculated.

[0121] Step Six: Calculate the error between the target equivalent blackbody temperature T_set and the current actual equivalent radiation temperature T_rad, i.e., e = T_set - T_rad. Then, input the error into the PID controller to obtain the corresponding correction coefficient α. The initial drive parameters of each transmitting unit are then corrected as a whole based on the correction coefficient. For example, when the initial drive parameter is a pulse width modulation duty cycle, the duty cycle of each transmitting unit can be updated as follows: D_new = D0 × (1 + α), and the corrected duty cycle is limited to a preset range, for example, between 0 and 1.

[0122] Step 7: Repeat steps 4 to 6, that is, update the driving parameters of each transmitting unit once in each frame period, and regenerate the row and column gating signals and PWM waveforms according to the updated driving parameters to continuously adjust the actual radiation output of the micro-transmitting unit array. For example, after 10 to 20 frames, or about 10 to 20 ms, the error e gradually decreases and approaches zero, entering a steady-state output state.

[0123] Step 8: If it is determined that the current actual equivalent radiation temperature has stabilized near the target equivalent blackbody temperature and the error meets the preset requirements, a "ready" signal is output to the external controller. At this time, the on-chip integrated infrared radiation source stably outputs infrared radiation corresponding to 100℃, which can be used for calibration measurement by the infrared temperature measuring device under test.

[0124] Step 9: When it is necessary to switch to a new target equivalent blackbody temperature, such as 50°C, steps 2 to 8 can be repeated. Because the thermal inertia of each transmitting unit is small, and this application can quickly update the initial driving parameters and implement feedback adjustment based on the new target equivalent blackbody temperature, the adjustment of the target radiation state can still be completed within milliseconds during temperature switching.

[0125] The aforementioned semiconductor calibration device, by setting up an on-chip integrated infrared radiation source, an optical interface aligned with the infrared temperature measuring device under test, and a control host communicatively connected to the on-chip integrated infrared radiation source, can provide the infrared temperature measuring device under test with a standard infrared radiation output corresponding to the target equivalent blackbody temperature, and achieve calibration control based on the status feedback of the on-chip integrated infrared radiation source and the measurement results of the device under test.

[0126] Compared to traditional calibration devices using cavity blackbody radiation sources, the semiconductor calibration device of this application has advantages such as smaller size, lower thermal inertia, faster response speed, and easier integration into production line testing stations, which is beneficial to improving the mass production calibration efficiency of infrared temperature probes in semiconductor process equipment. Furthermore, since the on-chip integrated infrared radiation source of this application can achieve rapid adjustment of radiation output within a preset wavelength band and the target equivalent blackbody temperature, it can also improve the matching with the actual operating wavelength of the infrared temperature measuring device under test and the consistency of the calibration process. Furthermore, through the coordinated operation between the host control unit, the on-chip integrated infrared radiation source, and the infrared temperature measuring device under test, this application can also achieve automated control and status feedback processing of the calibration process, thereby improving the stability and repeatability of the calibration device.

[0127] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0128] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. An on-chip integrated infrared radiation source, characterized in that, include: A semiconductor substrate having a suspended film region formed by back-side release; A micro-emission unit array is formed on the suspended membrane region, comprising multiple emission units arranged in an array. Each emission unit is an independent infrared radiation source and adopts a metal-dielectric-metal Fabry-Perot resonant cavity structure. The metal-dielectric-metal Fabry-Perot resonant cavity structure includes a bottom metal layer that also serves as a heating resistor, a dielectric spacer layer, and a top metal layer. The thickness of the dielectric spacer layer is configured to enable the corresponding emission unit to resonate in a preset wavelength band. A reference detection unit is formed on the suspended membrane region and is used to acquire monitoring information of the micro-emission unit array, including temperature status and / or radiation status; the reference detection unit has the same layer structure as the emission unit; The peripheral circuit is electrically connected to the micro-emitting unit array and the reference detection unit, respectively, and is used to process the output of the reference detection unit and drive the micro-emitting unit array according to the row-column interleaved addressing method; the peripheral circuit includes a storage unit, which is used to store the initial driving parameters of each of the transmitting units.

2. The on-chip integrated infrared radiation source according to claim 1, characterized in that, There are multiple reference detection units, and each reference detection unit is respectively disposed in the peripheral region and the central region of the micro-emission unit array.

3. The on-chip integrated infrared radiation source according to claim 2, characterized in that, The number of reference detection units is six, with four reference detection units respectively located in the four corner regions of the micro-emission unit array, and two reference detection units located near the center of the micro-emission unit array.

4. The on-chip integrated infrared radiation source according to claim 1, characterized in that, The bottom metal layer is patterned into a meandering shape to increase resistance and achieve electrothermal conversion.

5. The on-chip integrated infrared radiation source according to claim 1, characterized in that, The preset band range is 8–14 μm.

6. The on-chip integrated infrared radiation source according to claim 1, characterized in that, The top metal layer is a semi-transparent metal film used to achieve infrared radiation emission and optical field oscillation within the resonant cavity.

7. A method for controlling an infrared radiation source, characterized in that, The method applicable to the on-chip integrated infrared radiation source of any one of claims 1-6, the method comprising: Obtain the target's equivalent blackbody temperature and its corresponding target monitoring value; Based on the target equivalent blackbody temperature, the initial driving parameters corresponding to each of the transmitting units are obtained by querying the storage unit. Based on the initial driving parameters, row and column gating signals and pulse width modulation signals are generated to control the micro-emitting unit array, so that each of the emitting units generates heat and outputs infrared radiation. The monitoring information of the reference detection unit is obtained, and the real-time monitoring value corresponding to the array radiation state is determined based on the monitoring information. The drive correction parameters are determined based on the deviation between the real-time monitored value and the target monitored value; The initial driving parameters are corrected based on the driving correction parameters to obtain the target driving parameters for each transmitting unit; The micro-emission unit array is subjected to closed-loop drive control based on the target driving parameters to output infrared radiation corresponding to the target's equivalent blackbody temperature.

8. The method according to claim 7, characterized in that, The step of querying the storage unit to obtain the initial driving parameters corresponding to each of the transmitting units based on the target equivalent blackbody temperature includes: Individual calibration data corresponding to each of the transmitting units can be retrieved from the storage unit; the individual calibration data includes at least one of the following: the correspondence between driving parameters and radiation intensity, the correspondence between driving parameters and equivalent radiation temperature, and the correspondence between resistance value and temperature; Based on the target equivalent blackbody temperature, interpolation is performed on the individualized calibration data corresponding to each of the transmitting units to obtain the initial driving parameters corresponding to each of the transmitting units. The initial driving parameters include at least one of driving voltage, driving current, and pulse width modulation duty cycle.

9. The method according to claim 8, characterized in that, The individualized calibration data is constructed during the pre-calibration phase, and the construction methods include: Within a preset temperature range, a traceable blackbody is used as a reference to calibrate each of the aforementioned emission units point by point. Record the correspondence between the driving parameters and the equivalent radiation temperature of each of the aforementioned emission units at multiple calibrated temperature points; Based on the correspondence, individualized calibration data corresponding to each of the transmitting units is constructed, and the individualized calibration data is written into the storage unit.

10. The method according to claim 7, characterized in that, The step of generating row and column gating signals and pulse width modulation signals for controlling the micro-emission unit array based on the initial driving parameters includes: The micro-emission unit array is scanned according to a preset cycle and a preset sequence; For each selected row and / or column, a corresponding pulse width modulation signal is generated based on the initial driving parameters; The duty cycle of the pulse width modulation signal is determined based on the initial driving parameters to control the average heating power of each of the transmitting units and adjust the radiation intensity of each of the transmitting units.

11. The method according to claim 7, characterized in that, The monitoring information includes temperature monitoring data and radiation monitoring data; The reference detection unit operates in either temperature monitoring mode or radiation monitoring mode; The acquisition of the monitoring information of the reference detection unit includes: When the reference detection unit is operating in the temperature monitoring mode, no heating power is applied to each of the reference detection units, the resistance value of each of the reference detection units is detected at this time, and the temperature monitoring data is determined based on the resistance value. When the reference detection unit is operating in the radiation monitoring mode, a reverse bias is applied to each of the reference detection units, and the detection output of the reference detection unit is acquired to determine the radiation monitoring data of the adjacent area.

12. The method according to claim 11, characterized in that, The real-time monitored values ​​include real-time radiation status parameters; When the monitoring information includes temperature monitoring data, determining the real-time monitoring value corresponding to the array radiation state based on the monitoring information includes: Based on the temperature monitoring data and the preset thermal model, the real-time radiation state parameters corresponding to the micro-emission unit array are determined; The preset thermal model is used to characterize the relationship between the radiation power and temperature of the micro-emission unit array, whereby the radiation power is related to emissivity, radiation area, and temperature.

13. The method according to claim 8, characterized in that, The step of correcting the initial drive parameters based on the drive correction parameters to obtain the target drive parameters for each transmitting unit includes: The initial drive parameters of each of the transmitting units are corrected as a whole based on the drive correction parameters; the drive correction parameters are obtained by processing the deviation using a proportional-integral-derivative controller; By combining the individualized calibration data corresponding to each of the aforementioned launch units, the overall corrected drive parameters are corrected by unit-by-unit nonlinear mapping to obtain the target drive parameters of each of the aforementioned launch units.

14. The method according to claim 7, characterized in that, The method further includes: Detecting abnormal cells in the micro-emission unit array; If an abnormal unit is detected, the driving parameters of the transmitting units within a preset range around the abnormal unit are compensated and adjusted based on the driving parameters of at least one neighboring transmitting unit around the abnormal unit, so as to perform spatial interpolation compensation for the area where the abnormal unit is located.

15. The method according to claim 7, characterized in that, The method further includes: When the target equivalent blackbody temperature changes, the storage unit is queried based on the target equivalent blackbody temperature to obtain the updated initial driving parameters, and the updated initial driving parameters are used as feedforward control quantities to drive the micro-emission unit array to quickly approach the target radiation state. During the output radiation process, a driving correction parameter is determined based on the deviation between the real-time monitoring value and the target monitoring value, and the driving correction parameter is used as a feedback control quantity to dynamically adjust the micro-emission unit array.

16. A semiconductor calibration device, characterized in that, The device includes: The on-chip integrated infrared radiation source as described in any one of claims 1-6 is used to output infrared radiation corresponding to the target equivalent blackbody temperature using the control method of the infrared radiation source as described in any one of claims 7-15. An optical interface is used to align the infrared radiation output from the on-chip integrated infrared radiation source with the receiving optical path of the infrared temperature measuring device under test. The control host is communicatively connected to both the on-chip integrated infrared radiation source and the infrared temperature measuring device under test. It sends a set temperature to the on-chip integrated infrared radiation source to control the on-chip integrated infrared radiation source to output corresponding infrared radiation, and obtains the status feedback of the on-chip integrated infrared radiation source and the measurement results of the infrared temperature measuring device under test. It also calibrates the infrared temperature measuring device under test based on the set temperature, the status feedback, and the measurement results.

17. The apparatus according to claim 16, characterized in that, The device further includes: An external temperature control device is thermally connected to the on-chip integrated infrared radiation source and is used to adjust the operating temperature range of the on-chip integrated infrared radiation source.

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