An optical fiber grating wafer temperature sensor

Abstract

An optical fiber grating wafer temperature sensor, comprising: a substrate wafer; at least one first optical fiber, a part of which is provided with a plurality of temperature-sensing fiber gratings, and the temperature-sensing fiber gratings are arranged on the upper surface of the substrate wafer through a bonding material; the other part of the first optical fiber forms a transmission fiber connected to an optical wavelength detector and extends outside the substrate wafer. The optical fiber grating wafer temperature sensor of the present invention improves the service life and measurement accuracy of the wafer temperature sensor, and enables the temperature-sensing wafer and the wire part in the semiconductor process furnace to not contain metal components, having the characteristics of long service life, few connecting wires, and accurate temperature measurement.

Description

Technical Field

[0001] The present invention relates to an optical fiber temperature sensor, and particularly to an optical fiber grating wafer temperature sensor for measuring the two-dimensional temperature distribution in a process furnace during semiconductor manufacturing. Background Art

[0002] During the semiconductor processing and manufacturing process, many process steps, including etching, ion implantation, doping, chemical vapor deposition, physical vapor deposition, etc., require strict temperature measurement and control. The wafer temperature sensor is composed of multiple temperature sensors fixed at different positions on the wafer, which can measure the temperature distribution on the wafer plane, and then measure the two-dimensional temperature distribution in the process furnace. It is a device used for real-time and accurate temperature measurement during chip processing and manufacturing, and is an important tool in semiconductor equipment manufacturing and semiconductor production processes.

[0003] Most of the existing wafer temperature sensors are made of electronic temperature sensing devices such as thermocouples and thermal resistors. However, this kind of wafer temperature sensor composed of electronic devices has a limited service life and needs to be replaced or calibrated regularly. Each electronic temperature sensing device requires an independent metal wire to lead out. In the case of a large number of temperature measurement points, there are also many leads of the sensor, the manufacturing process is cumbersome, and it will also affect the accuracy of temperature measurement. In addition, when the wafer temperature sensor is in use, the wafer containing the temperature sensing device and part of the wires are in the process furnace. If the electronic temperature sensing device or the metal wire is not well sealed, the metal will volatilize in the high-temperature environment, affecting the quality of other semiconductor devices in the process furnace. Summary of the Invention

[0004] The purpose of the present invention is to provide an optical fiber grating wafer temperature sensor, which can improve the service life and measurement accuracy of the wafer temperature sensor, and enable the temperature sensing wafer and the wire part in the semiconductor process furnace not to contain metal components, having the characteristics of long service life, few connecting wires, and accurate temperature measurement.

[0005] To achieve the above object, the technical solution of the present invention is:

[0006] An optical fiber grating wafer temperature sensor, comprising: a substrate wafer; at least one first optical fiber, a part of which is provided with a plurality of temperature sensing fiber gratings, and the temperature sensing fiber gratings are arranged on the upper surface of the substrate wafer through a bonding material; the other part of the first optical fiber forms a transmission fiber connected to an optical wavelength detector and extends outside the substrate wafer.

[0007] Further, a strain compensation fiber grating is arranged on the lower surface of the substrate wafer corresponding to the position of the temperature sensing fiber grating fixed on the upper surface of the substrate wafer. The strain compensation fiber grating is arranged on a part of a second optical fiber, and the other part of the second optical fiber forms a transmission fiber connected to an optical wavelength detector and extends outside the substrate wafer.

[0008] Furthermore, a top cover wafer having the same shape as and the same material as the substrate wafer is fixed on the temperature-sensing fiber grating on the upper surface of the substrate wafer.

[0009] Also, a bottom cover wafer having the same shape as and the same material as the substrate wafer is fixed on the strain compensation fiber grating on the lower surface of the substrate wafer.

[0010] Preferably, the first optical fiber and / or the second optical fiber is / are one optical fiber or multiple optical fibers, and the temperature-sensing fiber grating or the strain compensation fiber grating is / are connected in series on one optical fiber or are respectively connected in series on multiple optical fibers.

[0011] Preferably, the temperature-sensing fiber grating includes at least one fiber grating; the strain compensation fiber grating includes at least one fiber grating. Preferably, the operating wavelengths of the fiber gratings on each optical fiber of the substrate wafer are different.

[0012] Preferably, the temperature-sensing fiber gratings connected in series on the first optical fiber are arranged in concentric circles on the upper surface of the substrate wafer. Preferably, the concentric circles are equidistantly arranged from each other and / or the temperature-sensing fiber gratings on each concentric circle are equidistantly arranged.

[0013] Preferably, the temperature-sensing fiber gratings on each concentric circle are equidistantly arranged, and the number of temperature-sensing fiber gratings on each concentric circle is the same, or the number of temperature-sensing fiber gratings arranged on the concentric circle closer to the edge of the substrate wafer is more than the number of temperature-sensing fiber gratings on the concentric circle closer to the center of the substrate wafer.

[0014] Preferably, the temperature-sensing fiber gratings on each concentric circle are equidistantly arranged, and the temperature-sensing fiber gratings on two adjacent concentric circles are arranged in alignment or are staggered by an angle.

[0015] Preferably, the temperature-sensing fiber gratings connected in series on the first optical fiber are arranged in equidistant parallel in the horizontal direction on the surface of the substrate wafer, and the temperature-sensing fiber gratings on each first optical fiber are equidistantly arranged.

[0016] Preferably, the positions of the temperature-sensing fiber gratings on two adjacent first optical fibers among the first optical fibers arranged in parallel are in alignment or are staggered by a distance.

[0017] Preferably, the temperature-sensing fiber gratings are arranged on several first optical fibers that are arranged in a radial pattern with equal angles from one point or several adjacent points on the edge of the substrate wafer surface to other points on the edge, and the temperature-sensing fiber gratings on each first optical fiber are equidistantly arranged along the axial direction.

[0018] Preferably, one or more first optical fibers with temperature-sensitive fiber gratings connected in series at equal angles and passing through the center of the circle are arranged on the surface of the substrate wafer, and the temperature-sensitive fiber gratings on each first optical fiber are arranged at equal intervals.

[0019] Preferably, the positions of the temperature-sensitive fiber gratings on two adjacent first optical fibers are arranged in alignment or offset by a certain distance.

[0020] Preferably, the temperature-sensitive fiber gratings are connected in series at equal intervals on the first optical fiber, and the first optical fiber with the temperature-sensitive fiber gratings connected in series is arranged on the surface of the substrate wafer in an Archimedean spiral.

[0021] Preferably, the temperature-sensitive fiber gratings are connected in series at equal intervals on the first optical fiber, and the first optical fiber with the temperature-sensitive fiber gratings connected in series is arranged on the surface of the substrate wafer in a Fermi spiral.

[0022] Preferably, the first optical fiber and the second optical fiber are doped quartz optical fibers, pure quartz optical fibers or sapphire optical fibers; the temperature-sensitive fiber grating is a fiber grating prepared on a doped quartz optical fiber by ultraviolet writing method, or a fiber grating prepared on a doped quartz optical fiber, pure quartz optical fiber or sapphire optical fiber by femtosecond writing method.

[0023] Preferably, the substrate wafer includes a silicon wafer, a silicon carbide wafer, a gallium nitride wafer or a gallium arsenide wafer.

[0024] Preferably, the bonding material includes epoxy glue, ceramic glue, silicon, silicon carbide, gallium nitride or gallium arsenide material.

[0025] In the present invention, a fiber grating is used as a temperature-sensing element, and an optical fiber is used as a transmission line. A plurality of fiber gratings are connected in series on the optical fiber, and these fiber gratings are arranged on the surface of the wafer to fabricate a fiber grating wafer temperature sensor with a long service life, fewer connecting wires and accurate temperature measurement.

[0026] The wavelength of the fiber grating changes linearly with temperature. When the temperature increases, the wavelength becomes larger; when the temperature decreases, the wavelength decreases. The real-time wavelength values of each temperature-sensitive fiber grating can be measured by an optical wavelength detector and converted into corresponding temperatures. According to the positions of each fiber grating arranged on the wafer, the real-time two-dimensional temperature distribution on the surface of the wafer can be obtained, so as to sense the real-time temperature distribution in the semiconductor process furnace where the fiber grating wafer temperature sensor is located.

[0027] The temperature-sensing fiber Bragg grating fixed on the substrate wafer can be a fiber Bragg grating fabricated on doped silica fiber by ultraviolet laser writing technology or femtosecond laser writing technology. The temperature range measured by such a fiber Bragg grating wafer temperature sensor can reach 400°C. The temperature-sensing fiber Bragg grating fixed on the substrate wafer can also be a fiber Bragg grating fabricated on pure silica fiber by femtosecond laser writing technology. The temperature range measured by such a fiber Bragg grating wafer temperature sensor can reach 1000°C. The temperature-sensing fiber Bragg grating fixed on the substrate wafer can also be a fiber Bragg grating fabricated on sapphire fiber by femtosecond laser writing technology. The temperature range measured by such a fiber Bragg grating wafer temperature sensor can reach 1800°C.

[0028] Since the fiber Bragg grating is an optical fiber device and its operating wavelength can remain stable for a long time, and the temperature-sensing fiber Bragg grating is fixed on the substrate wafer with a bonding material, the fiber Bragg grating wafer temperature sensor provided here can work stably for a long time and does not require regular calibration like an electronic wafer temperature sensor. Generally, the bandwidth of the operating wavelength of a fiber Bragg grating is about 0.2 nm, and the operating bandwidth of an optical wavelength detector can reach 80 nm. If the wavelength interval of the fiber Bragg gratings connected in series in a fiber is set to 0.8 nm, then one fiber can connect 80 fiber Bragg gratings. That is to say, one transmission fiber in the fiber Bragg grating wafer temperature sensor can transmit the signals of 80 temperature-sensing fiber Bragg gratings. Compared with some electronic wafer temperature sensors that use 160 wires to connect 80 electronic temperature sensors, the number of transmission lines is much less. Thus, the manufacturing process of the fiber Bragg grating wafer temperature sensor is simplified a lot and it is more convenient to use.

[0029] In the entire fiber Bragg grating wafer temperature sensor, the partial substrate wafer, temperature-sensing fiber Bragg grating, transmission fiber, and bonding material located inside the semiconductor process furnace do not contain metal components, and will not have an adverse impact on the wafers and other semiconductor devices inside the furnace, ensuring safe use. Just because the part of the fiber Bragg grating wafer temperature sensor inside the process furnace does not contain metal, the measurement result will not be affected by electromagnetic interference. In addition, using the wavelength of the temperature-sensing fiber Bragg grating as the signal for sensing temperature, the measurement result will not be affected by the fluctuation of the light source. Therefore, the fiber Bragg grating wafer temperature sensor provided by the present invention has the characteristic of accurate measurement.

[0030] In order to improve the temperature measurement accuracy, a strain compensation fiber Bragg grating can be arranged at the position on the lower surface of the substrate wafer corresponding to the upper surface of the substrate wafer where the temperature-sensing fiber Bragg grating points are arranged, which can compensate for the influence of the bending strain generated by uneven stress on the wafer on the temperature-sensing fiber Bragg grating, and obtain the change value of the fiber Bragg grating wavelength caused only by temperature change, so as to measure the temperature more accurately.

[0031] Compared with the wafer temperature sensors of the prior art, the fiber Bragg grating wafer temperature sensor provided by the present invention has the following advantages:

[0032] 1. Long service life and no need for regular calibration.

[0033] Fiber Bragg grating is a device formed by periodically perturbing the refractive index of the fiber core axially through means such as laser processing. This refractive index perturbation can be stably preserved under certain conditions. Moreover, fiber Bragg gratings generally undergo annealing treatment after being fabricated by laser processing. After annealing, the performance parameters of the fiber Bragg grating are basically stable. Without external force, the operating wavelength can remain unchanged for a long time in a certain temperature environment. Therefore, the fiber Bragg grating wafer temperature sensor using fiber Bragg grating as the temperature sensing element and the wavelength of the fiber Bragg grating as the temperature sensing signal can be used for a long time without regular calibration.

[0034] 2. Fewer lead wires and simple fabrication.

[0035] The periods of the refractive index perturbations in the fiber core of fiber Bragg gratings are different, and the operating wavelengths of the fiber Bragg gratings are also different. In addition, fiber Bragg gratings are compatible with optical fibers, and the connection losses between fiber Bragg gratings and between fiber Bragg gratings and optical fibers are extremely small. Therefore, dozens to hundreds of fiber Bragg gratings with different operating wavelengths can be fabricated or connected in series in one optical fiber. During demodulation, each fiber Bragg grating with a different operating wavelength in one optical fiber can be distinguished according to the wavelength division multiplexing technology. Therefore, multiple fiber Bragg gratings with different operating wavelengths can be connected in series on one transmission optical fiber in the fiber Bragg grating wafer sensor to jointly sense temperature. Compared with the electronic wafer temperature sensor in which each temperature sensing device requires 1 to 2 transmission wires, this greatly reduces the amount of signal transmission lines for the temperature sensing sensor and makes the fabrication process simpler.

[0036] 3. Accurate measurement.

[0037] On the one hand, the transmission optical fiber of the fiber Bragg grating wafer temperature sensor is small in volume and light in weight. Even if there are many temperature measurement points on the wafer, a small number of transmission optical fibers can be used without affecting the temperature distribution on the wafer, while the large number of metal wires in the electronic wafer temperature sensor with a large number of temperature measurement points may affect the temperature measurement result. On the other hand, fiber Bragg gratings are passive devices and are not affected by electromagnetic interference. In addition, the fiber Bragg grating wafer temperature sensor of the present invention uses the wavelength of the fiber Bragg grating as the parameter for sensing temperature, and the measurement result will not be affected by the fluctuation of the light source. Therefore, the fiber Bragg grating wafer temperature sensor of the present invention has the characteristic of accurate measurement.

[0038] 4. It will not cause adverse effects on the semiconductor process furnace and the devices inside the furnace.

[0039] In the fiber Bragg grating wafer temperature sensor, the substrate wafer, bonding material, adhesive, temperature-sensing fiber Bragg grating, and transmission fiber, which are in the semiconductor process furnace during operation, can all be metal-free materials. Even in a high-temperature environment or when the device has poor sealing, there will be no volatilization of metal substances that will have an adverse impact on the semiconductor devices in the process furnace. Brief Description of the Drawings

[0040] Figure 1 It is a cross-sectional view of Embodiment 1 of the present invention.

[0041] Figure 2 It is a cross-sectional view of Embodiment 2 of the present invention.

[0042] Figure 3 It is a cross-sectional view of Embodiment 3 of the present invention.

[0043] Figure 4 It is a cross-sectional view of Embodiment 4 of the present invention.

[0044] Figure 5 It is a top view of Embodiment 1 of the layout method of the temperature-sensing fiber Bragg grating in the fiber Bragg grating wafer temperature sensor of the present invention.

[0045] Figure 6 It is a top view of Embodiment 2 of the layout method of the temperature-sensing fiber Bragg grating in the fiber Bragg grating wafer temperature sensor of the present invention.

[0046] Figure 7 It is a top view of Embodiment 3 of the layout method of the temperature-sensing fiber Bragg grating in the fiber Bragg grating wafer temperature sensor of the present invention.

[0047] Figure 8 It is a top view of Embodiment 4 of the layout method of the temperature-sensing fiber Bragg grating in the fiber Bragg grating wafer temperature sensor of the present invention.

[0048] Figure 9 It is a top view of Embodiment 5 of the layout method of the temperature-sensing fiber Bragg grating in the fiber Bragg grating wafer temperature sensor of the present invention.

[0049] Figure 10 It is a top view of Embodiment 6 of the layout method of the temperature-sensing fiber Bragg grating in the fiber Bragg grating wafer temperature sensor of the present invention.

[0050] Figure 11 It is a top view of Embodiment 7 of the layout method of the temperature-sensing fiber Bragg grating in the fiber Bragg grating wafer temperature sensor of the present invention.

[0051] Figure 12 It is a top view of Embodiment 8 of the layout method of the temperature-sensing fiber Bragg grating in the fiber Bragg grating wafer temperature sensor of the present invention.

[0052] Figure 13This is a top view of the layout embodiment 9 of the temperature-sensitive fiber Bragg grating in the fiber Bragg grating wafer temperature sensor of the present invention.

[0053] Figure 14 This is a top view of the layout embodiment 10 of the temperature-sensitive fiber Bragg grating in the fiber Bragg grating wafer temperature sensor of the present invention.

[0054] Figure 15 This is a top view of the layout embodiment 11 of the temperature-sensitive fiber Bragg grating in the fiber Bragg grating wafer temperature sensor of the present invention. Detailed implementation manners

[0055] Refer to Figure 1 , the fiber Bragg grating wafer temperature sensor of the present invention includes:

[0056] A substrate wafer 1;

[0057] A first optical fiber 2, a part of which is provided with a plurality of temperature-sensitive fiber Bragg gratings 21, 22, and the temperature-sensitive fiber Bragg gratings 21, 22 are arranged on the upper surface of the substrate wafer 1 through a bonding material; another part of the first optical fiber 2 forms a transmission optical fiber 23 connected to an optical wavelength detector 100 and extends outside the substrate wafer 1.

[0058] Refer to Figure 2 , on the lower surface of the substrate wafer 1, strain compensation fiber Bragg gratings 31, 32 are arranged corresponding to the positions of the temperature-sensitive fiber Bragg gratings 21, 22 fixed on the upper surface of the substrate wafer 1. The strain compensation fiber Bragg gratings 31, 32 are arranged on a part of a second optical fiber 3, and another part of the second optical fiber 3 forms a transmission optical fiber 33 connected to the optical wavelength detector 100 and extends outside the substrate wafer 1.

[0059] Due to the relatively thin thickness of the substrate wafer, about 1 mm, and large diameter, with sizes of 100 mm, 200 mm, and 300 mm, if the placement position of the wafer sensor is not very flat, a certain part of the substrate wafer may be unevenly stressed and generate a small bending strain. This strain will cause the wavelength of the temperature-sensing fiber grating to change, affecting the temperature measurement accuracy. To correct the influence of the strain on the temperature measurement accuracy, strain-compensating fiber gratings are arranged on the lower surface of the substrate wafer. The strain-compensating fiber gratings are connected to the optical wavelength detector through the strain-compensating transmission fiber, and the optical wavelength detector can simultaneously detect the wavelengths of the temperature-sensing fiber grating and the strain-compensating fiber grating. The planar coordinates of the position where the strain-compensating fiber gratings are arranged on the lower surface of the substrate wafer are the same as those of the position where the temperature-sensing fiber gratings are arranged on the upper surface of the substrate wafer, and the arrangement direction of the strain-compensating fiber gratings is the same as the arrangement direction of the temperature-sensing fiber gratings on the substrate wafer. When the temperature changes, the wavelengths of both the temperature-sensing fiber grating and the strain-compensating fiber grating change in the same direction; when a bending strain occurs, the wavelength directions of the temperature-sensing fiber grating and the strain-compensating fiber grating are opposite and the magnitudes are the same; therefore, adding the wavelengths of the temperature-sensing fiber grating and the corresponding strain-compensating fiber grating can eliminate the influence of the bending strain and obtain the wavelength change amount related only to the temperature change, improving the measurement accuracy of the sensor.

[0060] See Figure 3 , a top cover wafer 4 with the same shape as the substrate wafer 1 and the same material as the substrate wafer 1 is fixed on the temperature-sensing fiber gratings 21 and 22 on the upper surface of the substrate wafer 1. To better protect the temperature-sensing fiber gratings 21 and 22 on the substrate wafer 1, a top cover wafer 4 is further adhesively fixed on the temperature-sensing fiber gratings 21 and 22, so that the temperature-sensing fiber gratings are protected from damage by external objects and the entire sensor is more reliable.

[0061] See Figure 4 , a bottom cover wafer 5 with the same shape as the substrate wafer 1 and the same material as the substrate wafer 1 is fixed on the strain-compensating fiber gratings 31 and 32 on the lower surface of the substrate wafer 1, which can prevent damage to the fiber gratings by external objects and improve the reliability and service life of the wafer temperature sensor.

[0062] Preferably, the first optical fiber and / or the second optical fiber is one optical fiber or multiple optical fibers, and the temperature-sensing fiber grating or the strain-compensating fiber grating is connected in series on one optical fiber or respectively connected in series on multiple optical fibers.

[0063] Preferably, the first optical fiber and the second optical fiber are doped quartz optical fibers, pure quartz optical fibers or sapphire optical fibers; the temperature-sensing fiber grating is a fiber grating prepared on the doped quartz optical fiber by ultraviolet writing method, or a fiber grating prepared on the doped quartz optical fiber, pure quartz optical fiber or sapphire optical fiber by femtosecond writing method.

[0064] Preferably, the substrate wafer includes a silicon wafer, a silicon carbide wafer, a gallium nitride wafer or a gallium arsenide wafer.

[0065] Preferably, the bonding material includes an epoxy adhesive, a ceramic adhesive, silicon, silicon carbide, gallium nitride or a gallium arsenide material.

[0066] See Figure 5 , in this embodiment, a temperature-sensitive fiber grating is arranged at the center of the substrate wafer 1; the temperature-sensitive fiber gratings connected in series on the first optical fiber are arranged in concentric circles on the upper surface of the substrate wafer. Preferably, the concentric circles are equidistantly arranged from each other and / or the temperature-sensitive fiber gratings on each concentric circle are equidistantly arranged.

[0067] Preferably, the temperature-sensitive fiber gratings on each concentric circle are equidistantly arranged, and the number of temperature-sensitive fiber gratings on each concentric circle is the same, or the number of temperature-sensitive fiber gratings arranged on the concentric circle closer to the edge of the substrate wafer is more than the number of temperature-sensitive fiber gratings on the concentric circle closer to the center of the substrate wafer, so as to increase the density of temperature measurement points.

[0068] As Figure 5 shown, 6 concentric circles are equally spaced from the center to the edge on the substrate wafer 1, 8 temperature-sensitive fiber gratings are arranged on each concentric circle, and the temperature-sensitive fiber gratings on the same concentric circle are arranged at positions where the horizontal radius of the concentric circle starts to be spaced at an angle of 45 degrees; the center point and the temperature-sensitive fiber gratings 21, 22 on each concentric circle are connected one by one with the first optical fiber 2, and the signals of the temperature-sensitive fiber gratings 21, 22 are led out by a transmission optical fiber 23.

[0069] See Figure 6 , in this embodiment, a temperature-sensitive fiber grating is arranged at the center of the substrate wafer 1; a series of concentric circles are equally spaced from the center to the edge of the substrate wafer 1 at a certain length, and temperature-sensitive fiber gratings are evenly arranged on these concentric circles. The number of temperature-sensitive fiber gratings on each concentric circle is the same, and the spacing between the temperature-sensitive fiber gratings on each concentric circle is the same.

[0070] As Figure 6 shown, 6 concentric circles are equally spaced from the center to the edge on the substrate wafer 1. 8 temperature-sensitive fiber gratings 21, 22 connected in series on the first optical fiber 2 are arranged on the 3 concentric circles closer to the center of the concentric circle, and the temperature-sensitive fiber gratings 21, 22 are arranged at intervals of 45 degrees circumferentially; 16 temperature-sensitive fiber gratings are arranged on the 3 concentric circles closer to the edge of the substrate wafer 1, and the temperature-sensitive fiber gratings 21, 22 are arranged at intervals of 22.5 degrees circumferentially; the signals of the temperature-sensitive fiber gratings 21, 22 are led out by a transmission optical fiber 23.

[0071] See Figure 7, in this embodiment, a temperature-sensing fiber grating is arranged at the center of the substrate wafer 1. The temperature-sensing fiber gratings 21 and 22 connected in series to the first optical fiber 2 draw a series of concentric circles at equal intervals from the center to the edge of the substrate wafer 1, and the temperature-sensing fiber gratings are evenly arranged on these concentric circles. The number of temperature-sensing fiber gratings on each concentric circle is the same, and the spacing between each temperature-sensing fiber grating on each circle is the same. The temperature-sensing fiber gratings on two adjacent concentric circles are staggered by a certain angle.

[0072] As Figure 7 shown, 6 concentric circles are drawn at equal intervals from the center to the edge on the substrate wafer 1, and 8 temperature-sensing fiber gratings 21 and 22 connected in series to the first optical fiber 2 are arranged on each concentric circle; the temperature-sensing fiber gratings on the 1st, 3rd, and 5th concentric circles starting from the center of the substrate wafer 1 are respectively distributed on the horizontal, vertical, and 45-degree-diameter azimuths of the substrate wafer; the temperature-sensing fiber gratings on the 2nd, 4th, and 6th concentric circles starting from the center of the substrate wafer are respectively distributed on the diameter azimuths at 22.5 degrees and 67.5 degrees to the horizontal diameter of the substrate wafer; the signals of the temperature-sensing fiber gratings 21 and 22 are led out by a transmission optical fiber 23.

[0073] See Figure 8 , in this embodiment, a temperature-sensing fiber grating is arranged at the center of the substrate wafer 1. The temperature-sensing fiber gratings 21 and 22 connected in series to the first optical fiber 2 draw a series of concentric circles at equal intervals from the center to the edge of the substrate wafer 1, and the spacing between each temperature-sensing fiber grating 21 and 22 on each concentric circle is the same; the temperature-sensing fiber gratings on two adjacent concentric circles are staggered by a certain angle.

[0074] As Figure 8 shown, the temperature-sensing fiber gratings 21 and 22 connected in series to the first optical fiber 2 draw 6 concentric circles at equal intervals from the center to the edge on the substrate wafer 1; 8 temperature-sensing fiber gratings are arranged on the 1st and 3rd concentric circles starting from the center of the substrate wafer 1 and are respectively distributed on the horizontal, vertical, and 45-degree-diameter azimuths of the substrate wafer. 8 temperature-sensing fiber gratings are arranged on the 2nd and 4th concentric circles starting from the center of the substrate wafer 1 and are respectively distributed on the diameter azimuths at 22.5 degrees and 67.5 degrees to the horizontal diameter of the substrate wafer 1. The signals of the temperature-sensing fiber gratings 21 and 22 are led out by a transmission optical fiber 23. 16 temperature-sensing fiber gratings are arranged at equal intervals on the 5th concentric circle and are evenly staggered by a certain angle from the temperature-sensing fiber gratings on the 4th concentric circle. 16 temperature-sensing fiber gratings are arranged at equal intervals on the 6th concentric circle and are evenly staggered by a certain angle from the temperature-sensing fiber gratings on the 5th concentric circle. The signals of the temperature-sensing fiber gratings 21 and 22 are led out by a transmission optical fiber 23.

[0075] See Figure 9, in this embodiment, the first optical fiber 2 with temperature-sensitive fiber Bragg gratings 21 and 22 connected in series forms several equally spaced parallel arrangements in the horizontal direction on the surface of the substrate wafer 1, and the temperature-sensitive fiber Bragg gratings 21 and 22 are arranged at equal intervals along the axial direction; the distances between adjacent two temperature-sensitive fiber Bragg gratings on each parallel line are the same and are aligned and distributed.

[0076] As Figure 9 shown, the first optical fiber 2 with temperature-sensitive fiber Bragg gratings 21 and 22 connected in series forms 8 equally spaced parallel arrangements in the horizontal direction on the surface of the substrate wafer 1. The signals of the temperature-sensitive fiber Bragg gratings 21 and 22 on the upper 4 optical fibers are led out by one transmission optical fiber 23, and the signals of the temperature-sensitive fiber Bragg gratings 21' and 22' on the other 4 optical fibers are led out by another transmission optical fiber 23'.

[0077] See Figure 10 , in this embodiment, the first optical fiber 2 with temperature-sensitive fiber Bragg gratings 21 and 22 connected in series forms several equally spaced parallel arrangements in the horizontal direction on the surface of the substrate wafer 1. The distances between adjacent two temperature-sensitive fiber Bragg gratings on each section of the optical fiber are the same, and the positions of the fiber Bragg gratings on adjacent two sections of the optical fiber are staggered by a certain distance; the signals of the temperature-sensitive fiber Bragg gratings 21 and 22 are all led out by one transmission optical fiber 23.

[0078] See Figure 11 , in this embodiment, the first optical fiber 2 with temperature-sensitive fiber Bragg gratings 21 and 22 connected in series takes a point or several adjacent points on the edge of the substrate wafer 1 as the starting point and is arranged radially at equal angles to other edges of the substrate wafer 1. The temperature-sensitive fiber Bragg gratings 21 and 22 are arranged at equal distances, and the signals of the temperature-sensitive fiber Bragg gratings on one optical fiber are respectively led out by one transmission optical fiber 23.

[0079] See Figure 12 , in this embodiment, the first optical fiber 2 with temperature-sensitive fiber Bragg gratings 21 and 22 connected in series takes the center of the substrate wafer 1 as the reference point, draws horizontal, vertical, and two diameter lines at a 45-degree angle to the horizontal direction, and the temperature-sensitive fiber Bragg gratings 21 and 22 are evenly arranged at equal intervals along these diameter lines.

[0080] See Figure 13 , in this embodiment, the first optical fiber 2 with temperature-sensitive fiber Bragg gratings 21 and 22 connected in series takes the center of the substrate wafer 1 as the reference point, draws horizontal, vertical, and two diameter lines at a 45-degree angle to the horizontal direction, and the temperature-sensitive fiber Bragg gratings 21 and 22 are evenly arranged at equal intervals along these diameter lines, and the positions of the temperature-sensitive fiber Bragg gratings on adjacent two diameter lines are staggered from each other.

[0081] See Figure 14, in this embodiment, the temperature-sensitive fiber gratings 21, 22 are connected in series at equal intervals on the first optical fiber 2, and the first optical fiber 2 is arranged on the substrate wafer 1 in the shape of an Archimedean spiral, and the fiber grating signal is led out through the transmission optical fiber 23.

[0082] See Figure 15 , in this embodiment, the temperature-sensitive fiber gratings 21, 22 are connected in series at equal intervals on the first optical fiber 2, and the first optical fiber 2 is arranged on the substrate wafer 1 in the shape of a Fermi spiral, and the fiber grating signal is led out through the transmission optical fiber 23.

Claims

1. An optical fiber grating wafer temperature sensor, characterized in that, include: A substrate wafer; at least one first optical fiber, a portion of which is provided with a plurality of temperature-sensitive optical fiber gratings, and the temperature-sensitive optical fiber gratings are arranged on the upper surface of the substrate wafer through a bonding material; Another part of the first optical fiber forms a transmission optical fiber connected to an optical wavelength detector and extends outside the substrate wafer; The temperature-sensitive fiber gratings connected in series to the first optical fiber are arranged in concentric circles on the upper surface of the substrate wafer; or, The first optical fiber connected in series with the temperature-sensitive optical fiber Bragg grating is bent in the horizontal direction of the substrate wafer surface to form a plurality of equally spaced parallel structures, and the temperature-sensitive optical fiber Bragg gratings on each section of the optical fiber are arranged at equal intervals; or, The first optical fiber connected in series with the temperature-sensitive fiber Bragg grating is arranged radially at equal angles from one edge point or several adjacent points on the surface of the substrate wafer to other points on the edge of the substrate wafer, and the temperature-sensitive fiber Bragg grating on each first optical fiber is arranged at equal intervals along the axial direction; or, one or more first optical fibers connected in series with the temperature-sensitive fiber Bragg grating are arranged at equal angles and through the center of a circle on the surface of the substrate wafer, and the temperature-sensitive fiber Bragg grating on each first optical fiber is arranged at equal intervals.

2. The fiber Bragg grating wafer temperature sensor according to claim 1, characterized in that, A strain compensating fiber grating is arranged on the lower surface of the substrate wafer at a position corresponding to the temperature-sensitive fiber grating fixed on the upper surface of the substrate wafer. The strain compensating fiber grating is arranged on a part of the second optical fiber, and the other part of the second optical fiber forms a transmission optical fiber connected to the optical wavelength detector and extends outside the substrate wafer.

3. The fiber Bragg grating wafer temperature sensor according to claim 1, wherein An upper cover plate wafer having the same shape and the same material as the substrate wafer is fixed on the temperature-sensitive optical fiber grating on the upper surface of the substrate wafer.

4. The fiber Bragg grating wafer temperature sensor as claimed in claim 2 or 3 or as described above, wherein, A lower cover wafer having the same shape and the same material as the substrate wafer is fixed on the strain compensation fiber grating on the lower surface of the substrate wafer.

5. The fiber Bragg grating wafer temperature sensor according to claim 1 or 2, characterized in that, The first optical fiber and / or the second optical fiber is one optical fiber or multiple optical fibers.

6. The fiber Bragg grating wafer temperature sensor according to claim 2, wherein, The temperature-sensitive fiber grating or the strain-compensating fiber grating is connected in series to one optical fiber, or is connected in series to a plurality of optical fibers respectively.

7. The fiber Bragg grating wafer temperature sensor according to claim 1 or 2, characterized in that, The temperature-sensitive fiber Bragg grating includes at least one fiber Bragg grating.

8. The fiber Bragg grating wafer temperature sensor according to claim 2, wherein The strain compensating fiber Bragg grating includes at least one fiber Bragg grating.

9. The fiber Bragg grating wafer temperature sensor according to claim 7, characterized in that The working wavelength of the fiber grating on each optical fiber of the substrate wafer is different.

10. The fiber Bragg grating wafer temperature sensor according to claim 8, wherein, The working wavelength of the fiber grating on each optical fiber of the substrate wafer is different.

11. The fiber Bragg grating wafer temperature sensor according to claim 1, characterized in that, The concentric circles are arranged at equal distances and / or the temperature-sensitive fiber gratings on each concentric circle are arranged at equal distances.

12. The fiber Bragg grating wafer temperature sensor according to claim 1 or 11, characterized in that, The temperature-sensitive fiber gratings on each concentric circle are arranged at equal intervals, and the number of temperature-sensitive fiber gratings on each concentric circle is the same, or the number of temperature-sensitive fiber gratings arranged on the concentric circle close to the edge of the substrate wafer is greater than the number of temperature-sensitive fiber gratings on the concentric circle close to the center of the substrate wafer.

13. The fiber Bragg grating wafer temperature sensor according to claim 1 or 11, characterized in that, The temperature-sensitive fiber gratings on each concentric circle are arranged at equal intervals, and the temperature-sensitive fiber gratings on two adjacent concentric circles are aligned or arranged at an angle to each other.

14. The fiber Bragg grating wafer temperature sensor according to claim 12, wherein, The temperature-sensitive fiber gratings on each concentric circle are arranged at equal intervals, and the temperature-sensitive fiber gratings on two adjacent concentric circles are aligned or arranged at an angle to each other.

15. The fiber Bragg grating wafer temperature sensor according to claim 1, characterized in that, In each section of the first optical fiber in the parallel arrangement structure, the temperature-sensitive fiber gratings on two adjacent optical fibers are arranged in alignment or staggered with each other by a certain distance.

16. The fiber Bragg grating wafer temperature sensor according to claim 1, characterized in that, The positions of the temperature-sensitive fiber gratings on two adjacent first optical fibers are arranged in alignment or staggered by a certain distance.

17. The fiber Bragg grating wafer temperature sensor according to claim 1, wherein The temperature-sensitive fiber gratings are connected in series at equal intervals on the first optical fiber, and the first optical fiber is arranged on the surface of the substrate wafer in an Archimedean spiral or a Fermi spiral.

18. The fiber Bragg grating wafer temperature sensor according to claim 1 or 2 or 3 or 6 or 8 or 9 or 10 or 11 or 14 or 15 or 16 or 17, characterized in that, The first optical fiber and the second optical fiber are doped quartz optical fibers, pure quartz optical fibers or sapphire optical fibers; the temperature-sensitive fiber grating is a fiber grating prepared on a doped quartz optical fiber by ultraviolet writing method, or a fiber grating prepared on a doped quartz optical fiber, a pure quartz optical fiber or a sapphire optical fiber by femtosecond writing method.

19. The fiber Bragg grating wafer temperature sensor according to claim 4, characterized in that, The first optical fiber and the second optical fiber are doped quartz optical fibers, pure quartz optical fibers or sapphire optical fibers; the temperature-sensitive fiber grating is a fiber grating prepared on a doped quartz optical fiber by ultraviolet writing method, or a fiber grating prepared on a doped quartz optical fiber, a pure quartz optical fiber or a sapphire optical fiber by femtosecond writing method.

20. The fiber Bragg grating wafer temperature sensor according to claim 5, characterized in that, The first optical fiber and the second optical fiber are doped quartz optical fibers, pure quartz optical fibers or sapphire optical fibers; the temperature-sensitive fiber grating is a fiber grating prepared on a doped quartz optical fiber by ultraviolet writing method, or a fiber grating prepared on a doped quartz optical fiber, a pure quartz optical fiber or a sapphire optical fiber by femtosecond writing method.

21. The fiber Bragg grating wafer temperature sensor according to claim 7, wherein The first optical fiber and the second optical fiber are doped quartz optical fibers, pure quartz optical fibers or sapphire optical fibers; the temperature-sensitive fiber grating is a fiber grating prepared on a doped quartz optical fiber by ultraviolet writing method, or a fiber grating prepared on a doped quartz optical fiber, a pure quartz optical fiber or a sapphire optical fiber by femtosecond writing method.

22. The fiber Bragg grating wafer temperature sensor according to claim 12, wherein The first optical fiber and the second optical fiber are doped quartz optical fibers, pure quartz optical fibers or sapphire optical fibers; the temperature-sensitive fiber grating is a fiber grating prepared on a doped quartz optical fiber by ultraviolet writing method, or a fiber grating prepared on a doped quartz optical fiber, a pure quartz optical fiber or a sapphire optical fiber by femtosecond writing method.

23. The fiber Bragg grating wafer temperature sensor according to claim 13, wherein The first optical fiber and the second optical fiber are doped quartz optical fibers, pure quartz optical fibers or sapphire optical fibers; the temperature-sensitive fiber grating is a fiber grating prepared on a doped quartz optical fiber by ultraviolet writing method, or a fiber grating prepared on a doped quartz optical fiber, a pure quartz optical fiber or a sapphire optical fiber by femtosecond writing method.

24. The fiber Bragg grating wafer temperature sensor according to claim 1 or 2 or 3 or 6 or 8 or 9 or 10 or 11 or 14 or 15 or 16 or 17, characterized in that, The substrate wafer includes a silicon wafer, a silicon carbide wafer, a gallium nitride wafer or a gallium arsenide wafer.

25. The fiber Bragg grating wafer temperature sensor according to claim 4, wherein The substrate wafer includes a silicon wafer, a silicon carbide wafer, a gallium nitride wafer or a gallium arsenide wafer.

26. The fiber Bragg grating wafer temperature sensor according to claim 5, wherein, The substrate wafer includes a silicon wafer, a silicon carbide wafer, a gallium nitride wafer or a gallium arsenide wafer.

27. The fiber Bragg grating wafer temperature sensor according to claim 12, wherein, The substrate wafer includes a silicon wafer, a silicon carbide wafer, a gallium nitride wafer or a gallium arsenide wafer.

28. The fiber Bragg grating wafer temperature sensor according to claim 13, wherein The substrate wafer includes a silicon wafer, a silicon carbide wafer, a gallium nitride wafer or a gallium arsenide wafer.

29. The fiber Bragg grating wafer temperature sensor according to claim 1, wherein The bonding material includes epoxy glue, ceramic glue, silicon, silicon carbide, gallium nitride or gallium arsenide material.

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