Special-shaped thermoelectric refrigerating unit, Dewar assembly, refrigerating infrared detector and composite refrigerating method

Abstract

The invention provides a special-shaped thermoelectric refrigerating unit, a Dewar assembly, a refrigerating infrared detector and a composite refrigerating method, and relates to the technical field of infrared detectors, the special-shaped thermoelectric refrigerating unit comprises a refrigerating unit body, the interior of the refrigerating unit body is hollow to form a cavity, and the longitudinal section of the refrigerating unit body is in an n shape; the cold end covers the top end of the n shape of the refrigerator body, and a first hole matched with the cavity is formed in the cold end; and the hot end is annularly enclosed on the side wall of the bottom of the n shape of the refrigerator body. The special-shaped thermoelectric refrigerator has the beneficial effects that the interior of the refrigerator body is hollow to form the cavity, and the longitudinal section of the refrigerator body is n-shaped, so that the special-shaped thermoelectric refrigerator can act on the edge area of a chip during working and can be combined with a refrigerator to realize composite refrigeration during application, and the whole chip is heated uniformly; the purposes of quickly refrigerating, optimizing the stress and deformation of the chip and ensuring the power consumption of the refrigerating machine are achieved, and meanwhile the temperature of the cold shield can be controlled.

Description

Technical Field

[0001] The invention relates to the technical field of infrared detectors, and in particular to a special-shaped thermoelectric cooler, a Dewar assembly, a refrigerated infrared detector and a composite refrigeration method. Background Art

[0002] As an important part of modern photoelectric detection technology, the core of cooled infrared detectors is the ability to efficiently and accurately reduce the focal plane temperature of the chip to an extremely low level. The operating temperature is usually required to be below 120K (Kelvin temperature, equivalent to -153.15℃) to ensure that the cooled infrared detector has high sensitivity and low noise performance.

[0003] The current mainstream cooling method for cooled infrared detectors is mostly cooling with a refrigerator. For large array infrared detectors or long array infrared detectors, this means a larger heat dissipation area and higher heat capacity. If a refrigerator is used alone for cooling, a larger cooling power consumption will be required. In addition, when facing large array chips or long array chips, due to the size of the cylinder, during the cooling process, the chip is unevenly heated, causing different parts of the chip to deform differently and eventually fail.

[0004] In addition, in existing products, support rods are often used to support the cooling infrared detector, which increases the thermal mass of the entire infrared detector, affects the cooling speed of the chip, and cannot quickly reduce the temperature of the filter. At the same time, the support components will consume a certain amount of heat, resulting in an increase in the power consumption of the refrigerator. During the process of cooling the chip by the refrigerator, a large part of the heat is absorbed by the cold screen, resulting in an increase in cooling power consumption and a longer cooling time. For long-line chip packaging, in order to reduce the gas temperature and increase its stability, the cold stage and fixed support are usually increased, resulting in more heat loss, and each chip cannot reach the operating temperature in the shortest time, affecting work efficiency. And when the infrared detector detects a target object at an extremely low temperature, the thermal noise from the cold screen and the filter will seriously affect the chip's recognition of the target and reduce the detector's working efficiency. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a special-shaped thermoelectric cooler, comprising:

[0006] A refrigerator body, wherein the interior of the refrigerator body is hollow to form a cavity and the longitudinal section is in the shape of a Chinese character "X";

[0007] A cold end, which is covered on the top of the "X" shape of the refrigerator body, and is provided with a first hole adapted to the cavity;

[0008] The hot end is annularly enclosed by the bottom side wall of the "X" shape of the refrigerator body.

[0009] Preferably, the refrigerator body comprises:

[0010] A plurality of groups of semiconductor devices, each group of semiconductor devices is arranged circumferentially to form the cavity at the center of each group of semiconductor devices, and each group of semiconductor devices is L-shaped;

[0011] A first metal guide bar, connected to the top of the L-shaped semiconductor device of each group, the first metal guide bar is provided with a second hole adapted to the cavity, and the cold end cover is arranged on the first metal guide bar;

[0012] The second metal conducting strip is annularly enclosed on the L-shaped bottom side wall of each group of the semiconductor devices, and the hot end is enclosed on the second metal conducting strip.

[0013] Preferably, each group of the semiconductor devices includes an N-type semiconductor and a P-type semiconductor, the N-type semiconductor and the P-type semiconductor are both L-shaped, and the outer side surface of the N-type semiconductor is stacked on the P-type semiconductor toward the inner side surface of the P-type semiconductor and forms a gap between the N-type semiconductor and the P-type semiconductor.

[0014] The present invention also provides a Dewar assembly, comprising:

[0015] A chip, wherein the edge area of ​​the lower end surface of the chip is attached to the cold end of the special-shaped thermoelectric cooler according to any one of claims 1 to 3;

[0016] A main cylinder, on which the hot end of the special-shaped thermoelectric cooler is fixed and passes through the main cylinder.

[0017] Preferably, it further comprises a substrate, the chip is fixed on the substrate, and the cold end of the special-shaped thermoelectric cooler is fixed on a side of the substrate away from the chip and below the edge area of ​​the lower end surface of the chip.

[0018] Preferably, the shape of the cold end matches the shape of the chip.

[0019] The present invention also provides a refrigerated infrared detector, comprising the above-mentioned Dewar assembly.

[0020] The present invention also provides a composite refrigeration method, which is applied to the above-mentioned refrigeration infrared detector, comprising:

[0021] Step S1, controlling the refrigerator to start to cool the chip in the cooling infrared detector;

[0022] Step S2, starting the special-shaped thermoelectric cooler to perform compound cooling on the edge area of ​​the chip.

[0023] Preferably, a first sensor is provided in the central area of ​​the chip, and a second sensor is provided in the edge area corresponding to the chip;

[0024] In the step S2, after starting the special-shaped thermoelectric refrigerator, the step further includes performing real-time operation control on the special-shaped thermoelectric refrigerator:

[0025] Step A1, pre-constructing a corresponding relationship table between the temperature difference range and the current and voltage;

[0026] Step A2, obtaining the real-time temperature difference between the real-time temperature of the central area detected by the first sensor and the real-time temperature of the edge area detected by the second sensor, and looking up the table to obtain the temperature difference range where the real-time temperature difference is located, and providing the current and voltage corresponding to the temperature difference range to the special-shaped thermoelectric cooler to control the real-time operation of the special-shaped thermoelectric cooler.

[0027] Preferably, the Dewar assembly of the refrigerated infrared detector further includes a cold shield, which is arranged above the chip, a filter is arranged on the top of the cold shield, and a third sensor is arranged on the side of the cold shield close to the filter;

[0028] The composite cooling method further includes controlling the special-shaped thermoelectric cooler to start when the real-time temperature of the cold screen detected by the third sensor is greater than a preset threshold.

[0029] The above technical solution has the following advantages or beneficial effects:

[0030] 1) The interior of the refrigerator body is hollow to form a cavity and the longitudinal section is in the shape of a "J", so that the special-shaped thermoelectric refrigerator can act on the edge area of ​​the chip when working, and can be combined with the refrigerator to achieve composite cooling when applied, so that the chip is heated evenly as a whole, achieving the purpose of rapid cooling and optimizing the stress and deformation of the chip and ensuring the power consumption of the refrigerator, and at the same time, the temperature of the cold screen can also be controlled;

[0031] 2) When the special-shaped thermoelectric cooler is installed inside the Dewar assembly, the cold end can be directly attached to the edge area of ​​the lower end surface of the chip, and because the cold end is non-conductive, it can replace the existing substrate, further reducing the thermal mass and improving the cooling rate;

[0032] 3) When the special-shaped thermoelectric cooler is installed inside the Dewar assembly, the hot end passes through the main tube, which can form natural convection heat dissipation with the air to dissipate the heat of the hot end, thereby accelerating the cooling rate of the cold end of the special-shaped thermoelectric cooler;

[0033] 4) When the special-shaped thermoelectric cooler is installed inside the Dewar assembly, the cold end fits the lower end surface of the chip, and the hot end is fixed and passes through the main tube, playing a supporting role, which can replace the existing support rod, not only reducing heat loss but also achieving the purpose of rapid cooling;

[0034] 5) At extremely low temperatures, special-shaped thermoelectric coolers can be used to quickly cool the cold screen and reduce the thermal noise that affects the operation of the chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a structural schematic diagram of a special-shaped thermoelectric cooler in a preferred embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of the internal structure of a refrigerator body in a preferred embodiment of the present invention;

[0037] Figure 3 This is a schematic diagram of the internal structure of the Dewar assembly in a preferred embodiment of the present invention;

[0038] Figure 4 In a preferred embodiment of the present invention, an exploded view of the Dewar assembly

[0039] Figure 5 This is a schematic diagram of the position of the chip and the cold end when the long-line chip is packaged in a preferred embodiment of the present invention;

[0040] Figure 6 The figure is a schematic flow chart of a composite refrigeration method in a preferred embodiment of the present invention;

[0041] Figure 7 It is a schematic diagram of a flow chart for real-time operation control of a special-shaped thermoelectric cooler in a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0042] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. The present invention is not limited to this embodiment, and other embodiments may also fall within the scope of the present invention as long as they conform to the gist of the present invention.

[0043] In a preferred embodiment of the present invention, based on the above problems existing in the prior art, a special-shaped thermoelectric cooler is provided. Figure 1 As shown, including:

[0044] A refrigerator body 1, wherein the interior of the refrigerator body 1 is hollow to form a cavity 11 and the longitudinal section is in the shape of a Chinese character "X";

[0045] The cold end 2 is covered on the top of the "X" shape of the refrigerator body 1, and a first hole 21 matching the cavity 11 is opened on the cold end 2;

[0046] The hot end 3 is annularly enclosed on the bottom side wall of the refrigerator body 1 in the shape of a cross.

[0047] Specifically, in this embodiment, the interior of the refrigerator body 1 is hollow to form a cavity 11, so that when it is installed under the chip, the edge area of ​​the chip can correspond to the cold end 2, and the center position of the chip can be exposed from the cavity 11, without affecting the existing refrigerator to cool the center position of the chip. At the same time, the special-shaped thermoelectric refrigerator can work with the refrigerator at the same time to achieve composite cooling of the center position and edge area of ​​the chip, which can make the chip heated evenly, while ensuring the power consumption of the refrigerator, achieving the purpose of rapid cooling and optimizing the stress and deformation of the chip.

[0048] In a preferred embodiment of the present invention, Figure 1 and Figure 2 As shown, the refrigerator body 1 includes:

[0049] A plurality of groups of semiconductor devices, each group of semiconductor devices is arranged circumferentially to form a cavity 11 at the center of each group of semiconductor devices, and each group of semiconductor devices is L-shaped;

[0050] The first metal conducting bar 12 is connected to the top of the L-shaped semiconductor device group. The first metal conducting bar 12 is provided with a second hole 121 adapted to the cavity 11. The cold end 2 is covered on the first metal conducting bar 12.

[0051] The second metal conducting strip 13 is annularly enclosed on the L-shaped bottom sidewall of each group of semiconductor devices, and the hot end 3 is enclosed on the second metal conducting strip 13 .

[0052] In a preferred embodiment of the present invention, each group of semiconductor devices includes an N-type semiconductor 14 and a P-type semiconductor 15, both of which are L-shaped, and the outer side surface of the N-type semiconductor 14 faces the inner side surface of the P-type semiconductor 15 and is stacked on the P-type semiconductor 15 to form a gap 16 between the N-type semiconductor 14 and the P-type semiconductor 15.

[0053] Specifically, in this embodiment, Figure 2 The upper and lower P-type semiconductors 15 and N-type semiconductors 14 are shown as a group, and the P-type semiconductors 15 and N-type semiconductors 14 are connected by the first metal guide bar 12 and the second metal guide bar 13, wherein the first metal guide bar 12 connects the top of the P-type semiconductor 15 and the N-type semiconductor 14, and the second metal guide bar 13 connects the bottom of the P-type semiconductor 15 and the N-type semiconductor 14, forming a circuit loop to ensure current conduction. The number of PN semiconductor groups can be selected according to the cooling time to achieve the purpose of lightweight and cost saving.

[0054] The present invention also provides a Dewar assembly, such as Figure 3 and Figure 4 As shown, including:

[0055] A chip 100, wherein the edge area of ​​the lower end surface of the chip 100 is attached to the cold end 2 of the special-shaped thermoelectric cooler according to any one of claims 1 to 3;

[0056] The main cylinder 200 , the hot end 3 of the special-shaped thermoelectric cooler is fixed on the main cylinder 200 and passes through the main cylinder 200 .

[0057] Specifically, in this embodiment, when the special-shaped thermoelectric cooler is installed inside the Dewar assembly, its cold end 2 fits the edge area of ​​the lower end surface of the chip 100, so that the edge area of ​​the chip can be cooled by the cold end 2. Among them, the cold end 2 can be bonded with glue with high thermal conductivity or by low-temperature brazing technology to fix it on the cold stage 300 and located at the edge area of ​​the lower end surface of the chip 100. Since the material of the cold end 2 is non-conductive, it can be used to replace the function of the existing substrate, so the substrate can be discarded according to actual needs, reducing the thermal mass and increasing the cooling rate.

[0058] like Figure 3 and Figure 4 As shown, the Dewar assembly also includes a cold shield 400 covering the chip 100, and a filter 500 is provided on the top of the cold shield 400. The cold stage 300 and the special-shaped thermoelectric cooler and the cold shield 400 below are all arranged in the Dewar window 600, and a window 700 is provided on the top of the Dewar window 600 corresponding to the position of the filter 500. A cylinder 800 is also provided inside the main barrel 200.

[0059] Furthermore, the hot end 3 of the special-shaped thermoelectric cooler is welded and fixed on the main tube 200 and passes through the main tube 200, so that the hot end 3 can form natural convection heat dissipation with the air to dissipate the heat of the hot end 3, thereby accelerating the cooling rate of the cold end 2.

[0060] In a preferred embodiment of the present invention, a substrate is further included, the chip is fixed on the substrate, and the cold end of the special-shaped thermoelectric cooler is fixed on a side of the substrate away from the chip and below the edge area of ​​the lower end surface of the chip.

[0061] Specifically, in this embodiment, the substrate may not be discarded in actual application scenarios, and the cold end may be fixed on the substrate, and composite cooling of the chip can also be achieved together with the refrigerator.

[0062] In a preferred embodiment of the present invention, the shape of the cold end 2 matches the shape of the chip 100 .

[0063] Specifically, in this embodiment, the shape of the cold end 2 can be customized according to the needs, and only the first hole 21 needs to be reserved and the top of each group of semiconductor devices can be connected. By modifying the shape of the cold end 2 accordingly based on the shape of the chip or substrate, it can ensure that the cold end 2 and the chip 100 are perfectly matched, thereby improving the cooling efficiency.

[0064] The present invention also provides a refrigerated infrared detector, comprising the above-mentioned Dewar assembly.

[0065] Specifically, in this embodiment, the cooling infrared detector is preferably a large array infrared detector or a long line array infrared detector, which can significantly reduce the cooling power consumption of the refrigerator. Figure 5 As shown, it is a schematic diagram of the position of the chip and the cold end when the long-line chip is packaged.

[0066] The present invention also provides a composite refrigeration method, which is applied to the above-mentioned refrigeration infrared detector, such as Figure 6 As shown, including:

[0067] Step S1, controlling the refrigerator to start up to cool the chip in the infrared detector;

[0068] Step S2, starting the special-shaped thermoelectric cooler to perform compound cooling on the edge area of ​​the chip.

[0069] Specifically, in this embodiment, by starting the special-shaped thermoelectric cooler when the refrigerator is turned on, it is ensured that the center and the periphery of the chip or substrate are heated evenly, thereby reducing its deformation and reducing the impact on the chip.

[0070] In a preferred embodiment of the present invention, a first sensor is provided in the central area of ​​the chip, and a second sensor is provided in the edge area corresponding to the chip;

[0071] In step S2, after starting the special-shaped thermoelectric cooler, Figure 7 As shown, it also includes real-time operation control of special-shaped thermoelectric coolers:

[0072] Step A1, pre-constructing a corresponding relationship table between the temperature difference range and the current and voltage;

[0073] Step A2, obtaining the real-time temperature difference between the real-time temperature of the central area detected by the first sensor and the real-time temperature of the edge area detected by the second sensor, and looking up the table to obtain the temperature difference range where the real-time temperature difference is located, and providing the special-shaped thermoelectric cooler with current and voltage corresponding to the temperature difference range to control the real-time operation of the special-shaped thermoelectric cooler.

[0074] Specifically, in this embodiment, the real-time temperatures of the central area and the edge area of ​​the chip are respectively detected by the first sensor and the second sensor, so as to obtain the overall thermal distribution of the chip, and then control the current and voltage of the special-shaped thermoelectric cooler to ensure that the overall chip is heated evenly each time it is started.

[0075] Among them, the first sensor is the temperature sensor that comes with the chip. When a substrate is provided in the cooling infrared sensor, the second sensor is installed on the substrate and corresponds to the edge area of ​​the chip. When no substrate is provided, the second sensor is installed on the cold platform and corresponds to the edge area of ​​the chip. This is not limited here.

[0076] In a preferred embodiment of the present invention, the Dewar assembly of the refrigerated infrared detector further includes a cold shield, which is arranged above the chip, a filter is arranged on the top of the cold shield, and a third sensor is arranged on the side of the cold shield close to the filter;

[0077] The composite cooling method also includes controlling the special-shaped thermoelectric cooler to start when the real-time temperature of the cold screen detected by the third sensor is greater than a preset threshold.

[0078] Specifically, in this embodiment, when it is detected that the temperature of the cold screen is high, the special-shaped thermoelectric cooler can be started to cool it down, reduce its thermal noise, and improve the working efficiency of the chip.

[0079] The above description is only a preferred embodiment of the present invention, and does not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the contents of this specification and illustrations should be included in the protection scope of the present invention.

Claims

1. A special-shaped thermoelectric cooler, characterized in that: include: A refrigerator body, wherein the interior of the refrigerator body is hollow to form a cavity and the longitudinal section is in the shape of a Chinese character "X"; A cold end, which is covered on the top of the "X" shape of the refrigerator body, and is provided with a first hole adapted to the cavity; The hot end is annularly enclosed by the bottom side wall of the "X" shape of the refrigerator body.

2. The special-shaped thermoelectric cooler according to claim 1, characterized in that: The refrigerator body comprises: A plurality of groups of semiconductor devices, each group of semiconductor devices is arranged circumferentially to form the cavity at the center of each group of semiconductor devices, and each group of semiconductor devices is L-shaped; A first metal guide bar, connected to the top of the L-shaped semiconductor device of each group, the first metal guide bar is provided with a second hole adapted to the cavity, and the cold end cover is arranged on the first metal guide bar; The second metal conducting strip is annularly enclosed on the L-shaped bottom side wall of each group of the semiconductor devices, and the hot end is enclosed on the second metal conducting strip.

3. The special-shaped thermoelectric cooler according to claim 2, characterized in that: Each group of semiconductor devices includes an N-type semiconductor and a P-type semiconductor, wherein the N-type semiconductor and the P-type semiconductor are both L-shaped, and the N-type semiconductor is stacked on the P-type semiconductor with the outer side surface facing the inner side surface of the P-type semiconductor and forming a gap between the N-type semiconductor and the P-type semiconductor.

4. A Dewar assembly, characterized in that: include: A chip, wherein the edge area of ​​the lower end surface of the chip is attached to the cold end of the special-shaped thermoelectric cooler according to any one of claims 1 to 3; A main cylinder, on which the hot end of the special-shaped thermoelectric cooler is fixed and passes through the main cylinder.

5. The Dewar assembly according to claim 4, characterized in that: It also includes a substrate, the chip is fixed on the substrate, and the cold end of the special-shaped thermoelectric cooler is fixed on a side of the substrate away from the chip and below the edge area of ​​the lower end surface of the chip.

6. The Dewar assembly according to claim 4, characterized in that: The shape of the cold end is adapted to the shape of the chip.

7. A refrigerated infrared detector, characterized in that: The invention comprises the Dewar assembly as claimed in claim 4.

8. A composite refrigeration method, characterized in that: The refrigerated infrared detector according to claim 7 comprises: Step S1, controlling the refrigerator to start to cool the chip in the cooling infrared detector; Step S2, starting the special-shaped thermoelectric cooler to perform compound cooling on the edge area of ​​the chip.

9. The compound refrigeration method according to claim 8, characterized in that: A first sensor is disposed in the central area of ​​the chip, and a second sensor is disposed in the edge area corresponding to the chip; In the step S2, after starting the special-shaped thermoelectric refrigerator, the step further includes performing real-time operation control on the special-shaped thermoelectric refrigerator: Step A1, pre-constructing a corresponding relationship table between the temperature difference range and the current and voltage; Step A2, obtaining the real-time temperature difference between the real-time temperature of the central area detected by the first sensor and the real-time temperature of the edge area detected by the second sensor, and looking up the table to obtain the temperature difference range where the real-time temperature difference is located, and providing the current and voltage corresponding to the temperature difference range to the special-shaped thermoelectric cooler to control the real-time operation of the special-shaped thermoelectric cooler.

10. The compound refrigeration method according to claim 8, characterized in that: The Dewar assembly of the refrigerated infrared detector also includes a cold shield, which is arranged above the chip, a filter is arranged on the top of the cold shield, and a third sensor is arranged on the side of the cold shield close to the filter; The composite cooling method further includes controlling the special-shaped thermoelectric cooler to start when the real-time temperature of the cold screen detected by the third sensor is greater than a preset threshold.

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