A large-size low-power thermoelectric refrigerator with good reliability and a manufacturing method thereof

Abstract

The application discloses a large-size low-power thermoelectric refrigerator with good reliability and a manufacturing method thereof, and overcomes the problem that the size, reliability and power consumption of a thermoelectric refrigerator cannot coexist in the prior art. The thermoelectric refrigerator comprises two ceramic substrates in an up-down structure, semiconductor particles and heat insulation particles which do not participate in refrigeration and are only used for supporting are arranged between the two ceramic substrates, and the inner surfaces of the ceramic substrates are provided with a plurality of flow guide fins, and the flow guide fins corresponding to the positions of the heat insulation particles are provided with through holes. The heat insulation particles which only play a supporting role are added, and the through holes are formed in the corresponding flow guide fins of the heat insulation particles, so that the heat transfer thermal resistance is maximally increased, heat short circuit is prevented, and the power consumption and the reliability are good.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor refrigeration, in particular to a large-size low-power thermal-electric cooler with good reliability and a manufacturing method thereof. BACKGROUND

[0002] With the rapid development of vehicle-mounted radar / optical communication industry, customers' demand for product power consumption and reliability is increasing, which also brings the contradiction between high reliability and low power consumption of TEC (Thermal-electric cooler) increasingly prominent. When customers are limited by installation and other factors, the size of TEC cannot be changed, and when selecting TEC according to customer working conditions, the product needs less power, which will cause poor product reliability according to conventional design, but improving reliability will correspondingly increase the power consumption of the device, causing waste.

[0003] The refrigeration principle of TEC is the Peltier effect, and the reliability of TEC in operation is directly related to the cross-sectional area of the semiconductor particles. The conventional means to improve reliability is the maximum current of semiconductor particles Imax / semiconductor particle logarithm / material performance, and the former two will inevitably increase the power consumption, and if only the particle logarithm is increased without power, it will also cause a thermal short circuit. The current conventional solution is to sacrifice reliability / power consumption according to the actual application of the customer.

[0004] Conventional solution description: Currently, additional particles are mainly used, but the material is still bismuth telluride, which plays a supporting role but has no heat insulation effect. According to the law of thermodynamics, heat will spontaneously flow from the heat dissipation surface substrate to the heat absorption surface substrate, causing a thermal short circuit and greatly reducing the refrigeration effect. If the particles 4 are powered, the overall power consumption of the TEC will necessarily increase. Another solution is to sacrifice reliability to meet the power consumption demand without additional heat-insulating particles that only play a supporting role. Neither of them solves the problem of coexistence of low power consumption, large size, and reliability. SUMMARY

[0005] The purpose of the present application is to overcome the problem of the coexistence of the size, reliability, and power consumption of the thermal-electric cooler in the prior art, and to provide a large-size low-power thermal-electric cooler with good reliability and a manufacturing method thereof. The heat-insulating particles only play a supporting role, and holes are opened on the corresponding flow guide pieces of the heat-insulating particles to maximize the thermal resistance, prevent thermal short circuit, and ensure good power consumption and reliability.

[0006] In order to achieve the above purpose, the present application adopts the following technical scheme: a large-size low-power thermal-electric cooler with good reliability, comprising:

[0007] The two ceramic substrates of the upper and lower structure are provided with semiconductor particles for refrigeration and heat insulation particles for support only, and the inner surfaces of the ceramic substrates are provided with a plurality of flow guides, and the flow guides corresponding to the positions of the heat insulation particles are provided with through holes.

[0008] The heat insulation particles do not participate in refrigeration, and when the thermoelectric module is powered on, the current does not flow through the heat insulation particles, that is, the heat insulation particles only play a supporting role, thereby improving the reliability of the product. The flow guides corresponding to the heat insulation particles are provided with through holes to increase the thermal resistance between the copper electrodes and the semiconductor particles, thereby avoiding thermal short circuit. The application increases the heat insulation particles which only play a supporting role, and adopts the through holes in the corresponding flow guides of the heat insulation particles, thereby maximally increasing the heat transfer resistance, preventing thermal short circuit, ensuring good power consumption and reliability, and realizing the coexistence of large size, reliability and low power consumption.

[0009] As a preferred, the semiconductor particles include P-type semiconductor particles and N-type semiconductor particles, and the P-type semiconductor particles and the N-type semiconductor particles form P / N junctions.

[0010] The semiconductor particles are arranged between the two ceramic substrates in series and are connected with the flow guides to form a refrigeration circuit. The semiconductor particles are not uniformly distributed, and part of the particles are not connected with the circuit. The distribution of the semiconductor particles can be adjusted according to the position of the actual heating component, thereby minimizing the waste of refrigeration capacity.

[0011] As a preferred, the semiconductor particles and the heat insulation particles are fixedly connected by tin soldering, the heat insulation particles only have tin on the surface during welding, and there is no tin in the hole; the flow guides and the ceramic are connected by epoxy adhesive bonding; and the flow guides and the heat insulation particles are connected by bonding. The epoxy adhesive bonding is adopted to increase the contact thermal resistance.

[0012] As a preferred, round holes are etched on the flow guides, and the middle region of the heat insulation particles does not directly contact the heat conduction sheet, thereby reducing the thermal stress generated by the heat insulation particles during work.

[0013] The contact area between the heat insulation particles and the flow guides is small, the heat transfer thermal resistance is large, and the risk of thermal short circuit is low; meanwhile, the heat insulation particles and the center hole position of the flow guides are not in contact, and pores will appear during welding, thereby increasing the thermal resistance between the flow guides and the heat insulation particles and reducing heat loss.

[0014] As a preferred, the heat insulation particles are made of high-strength resin material, and the surface of the heat insulation particles is plated with a nickel-tin layer, thereby having good weldability.

[0015] As a preferred, the ceramic substrate located at the upper position is made of aluminum nitride ceramic. The temperature difference of the cold surface substrate caused by the uneven distribution of the semiconductor particles is reduced.

[0016] A method for manufacturing a large-size low-power thermoelectric refrigerator with good reliability, comprising the following steps:

[0017] S1: manufacturing a flow guide piece, an upper substrate and a lower substrate;

[0018] S2: printing a layer of tin paste on the upper substrate and the lower substrate, placing semiconductor particles and heat insulation particles at corresponding positions on the lower substrate, and covering the upper substrate;

[0019] S3: tightly fixing the upper substrate and the lower substrate, and using a heating device to complete the welding process;

[0020] S4: cooling and cleaning the welded product to obtain a thermoelectric refrigerator.

[0021] The flow guide piece is generally copper-based, and whether to be lined with nickel and plated with gold is selected according to needs; the tin paste at the corresponding position of the open flow guide piece cannot flow into the hole.

[0022] As preferred, the step S1 further comprises:

[0023] The copper sheet and the ceramic sheet are connected through AMB or DBC technology, the copper surface is etched to form a customized shape of the flow guide piece, and then the substrate is obtained after cleaning.

[0024] DBC technology refers to heating at a high temperature of about 1063 DEG C in nitrogen containing oxygen, and directly welding a layer of copper foil on the surface of alumina or aluminum nitride ceramic. AMB active copper brazing process is to use a small amount of active elements contained in the filler metal to react with the ceramic to form a reaction layer that can be wetted by liquid filler metal, so as to realize the joint of ceramic and metal.

[0025] As preferred, the step S2 further comprises: arranging the semiconductor particles in series between the upper substrate and the lower substrate, welding the semiconductor particles on the flow guide piece through tin soldering to form a refrigeration circuit, and welding the heat insulation particles on the flow guide piece through tin soldering. The heat insulation particles do not participate in refrigeration and only play a supporting role.

[0026] Therefore, the present invention has the following beneficial effects: 1. By adding heat-insulating particles that only serve a supporting function and by opening holes in the corresponding flow guide plates of the heat-insulating particles, the thermal resistance is maximized, preventing thermal short circuits and ensuring good power consumption and reliability, while also taking into account the characteristics of large size, low power, and high reliability; 2. The distribution of semiconductor particles can be adjusted according to the actual position of the heat-generating components, minimizing the waste of cooling capacity; 3. The openings in the flow guide plates of the product prevent the central area of ​​the heat-insulating particles from directly contacting the flow guide plates, reducing the thermal stress generated by the heat-insulating particles during operation; 4. The heat-insulating particles that do not participate in cooling do not contact the central hole of the flow guide plate, which will cause pores during welding, increasing the thermal resistance between the flow guide plate and the heat-insulating particles, reducing heat loss. The small contact area between the heat-insulating particles and the flow guide plate results in a larger thermal resistance and a lower risk of thermal short circuits. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of the thermoelectric cooler in this invention.

[0028] Figure 2 This is a top view of the upper substrate structure in this invention.

[0029] Figure 3 This is a top view of the lower substrate structure in this invention.

[0030] Figure 4 This is a schematic diagram of the contact between the semiconductor particles and the current-conducting plate in this invention.

[0031] Figure 5 This is a schematic diagram of the current flow direction in the thermoelectric cooler of this invention.

[0032] In the diagram: 1. Upper substrate; 2. Semiconductor particles; 3. Conventional flow guide plate; 4. Heat insulation particles; 5. Lower substrate; 6. Opening flow guide plate. Detailed Implementation

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0034] This embodiment describes a large-size, low-power thermoelectric cooler with high reliability, such as... Figure 1 As shown, it includes two ceramic substrates with an upper and lower structure, namely an upper substrate 1 located above and a lower substrate 5 located below. Semiconductor particles 2 and heat-insulating particles 4 that do not participate in cooling but are only used for support are installed between the upper and lower substrates.

[0035] Among them, such as Figure 2 and Figure 3 As shown, guide vanes are provided on the inner surfaces (the opposing surfaces of the upper and lower substrates) of both the upper and lower substrates. Figure 4As shown (thermoelectric cooler top view), the guide vane includes a conventional guide vane 3 and an open hole guide vane 6 provided with a through hole, and the open hole guide vane is opposite to the position of the heat insulation particles (that is, the through hole is provided on the guide vane on the inner surface of the upper polar plate and the inner surface of the lower polar plate opposite to the position of the heat insulation particles), and the conventional guide vane is opposite to the position of the semiconductor particles.

[0036] The heat insulation particles do not participate in refrigeration, and when the thermoelectric module is powered on, the current does not flow through the heat insulation particles, that is, the heat insulation particles only play a supporting role, and the product reliability is improved. The through hole is provided on the guide vane corresponding to the heat insulation particles to increase the thermal resistance between the copper electrode and the semiconductor particles, and to avoid thermal short circuit.

[0037] The application increases the heat insulation particles which only play a supporting role, and adopts the open hole on the guide vane corresponding to the heat insulation particles, maximally increases the heat transfer resistance, prevents thermal short circuit, and ensures good power consumption and reliability; meanwhile, the characteristics of large size, low power and high reliability are considered.

[0038] In the embodiment, the semiconductor particles include P-type semiconductor particles and N-type semiconductor particles, and the P-type semiconductor particles and the N-type semiconductor particles form a P / N junction.

[0039] The semiconductor particles are arranged between the two ceramic substrates in series and are connected with the guide vanes to form a refrigeration circuit. The semiconductor particles are not uniformly distributed, and part of the particles are not connected with the circuit. The distribution of the semiconductor particles can be adjusted according to the position of the actual heat generating component, so as to minimize the waste of refrigeration capacity.

[0040] The semiconductor particles and the heat insulation particles are connected and fixed by means of soldering, and only the contact surface has tin, and there is no tin in the hole during welding; the connection mode of the heat insulation particles and the guide vanes can be adhesion, so as to increase the thermal resistance; the connection mode of the open hole guide vane and the ceramic substrate can adopt epoxy adhesion, so as to increase the contact thermal resistance, and the sintering mode can also be adopted; the semiconductor particles are welded on the guide vanes by soldering to form a refrigeration circuit, and there is no tin in the hole of the guide vanes, and only the contact part has tin. As shown, the arrow indicates the current flow direction, and it can be seen that the semiconductor particles are not uniformly distributed, and part of the particles are not connected with the circuit. In order to more directly see the effect, Figure 5 the heat insulation particles which only play a supporting role are hidden in the middle. Figure 5

[0041] The upper substrate material can be set as aluminum nitride ceramic, so as to minimize the temperature difference of the cold surface substrate caused by the uneven distribution of the semiconductor particles; the heat insulation particles which do not participate in refrigeration are made of low thermal conductivity and high strength resin material, and the surface is plated with a nickel-tin layer, and the solderability is good.

[0042] ​At the same time, because the heat insulation particles are opposite to the open hole flow guide piece, the middle region of the heat insulation particles is not in direct contact with the flow guide piece, so that the thermal stress generated by the heat insulation particles in operation can be reduced; the heat insulation particles not participating in refrigeration are not in contact with the center hole position of the open hole flow guide piece, and pores will appear during welding, so that the thermal resistance between the flow guide piece and the heat insulation particles is increased, and the heat loss is reduced; the heat insulation particles not participating in refrigeration have a small contact area with the flow guide piece, the heat transfer thermal resistance is large, and the risk of thermal short circuit is low.

[0043] The embodiment also provides a large-size low-power thermoelectric refrigerator manufacturing method with good reliability, comprising the following steps:

[0044] First step: manufacturing the flow guide piece, the upper substrate and the lower substrate.

[0045] The flow guide piece is generally copper-based, and whether nickel plating and gold plating are selected according to needs. First, the copper sheet and the ceramic sheet are connected through AMB or DBC technology, then the copper surface is etched according to needs to form a customized shape of the flow guide piece, and then the flow guide piece is cleaned. The upper substrate and the lower substrate are manufactured in the same way, and thus the manufacturing of the upper substrate and the lower substrate is completed.

[0046] Second step: printing a layer of tin paste on the upper substrate and the lower substrate, placing semiconductor particles and heat insulation particles on the lower substrate at corresponding positions, and covering the upper substrate.

[0047] Before assembly, a layer of tin paste is printed on the upper substrate and the lower substrate respectively, and special attention is paid to the fact that the tin paste at the corresponding position of the open hole flow guide piece cannot flow into the hole, then the semiconductor particles and the heat insulation particles are placed on the lower substrate at the corresponding positions, and then the upper substrate is covered. The flow guide piece includes an open hole flow guide piece and a non-open hole flow guide piece, and the open hole flow guide piece corresponds to the position of the heat insulation particle.

[0048] The distribution of the semiconductor particles can be adjusted according to the position of the actual heat generating component, so as to minimize the waste of refrigeration capacity.

[0049] Third step: tightly fixing the upper substrate and the lower substrate, and using a heating device to complete the welding process.

[0050] The upper and lower substrates are clamped and fixed by using a special jig, and are sent into a heating device to complete the welding process, so as to realize the connection between the substrates and the semiconductor components.

[0051] Fourth step: cooling and cleaning the welded product to obtain a thermoelectric refrigerator.

[0052] The above-described embodiment is only a preferred scheme of the present application, and does not limit the present application in any form, and other variants and modifications can be made without exceeding the technical scheme recited in the claims.

Claims

1. A large-sized low-power thermoelectric refrigerator with high reliability, characterized by comprising: Two ceramic substrates with upper and lower structures, semiconductor particles for refrigeration and heat insulation particles for support only are arranged between the two ceramic substrates, inner surfaces of the ceramic substrates are provided with a plurality of flow guides, through holes are arranged on the flow guides corresponding to positions of the heat insulation particles, and the heat insulation particles are not in direct contact with the flow guides; the semiconductor particles are arranged in series between the ceramic substrates and connected with the flow guides.

2. The large size low power thermoelectric refrigerator with good reliability according to claim 1, wherein The semiconductor particles include P-type semiconductor particles and N-type semiconductor particles, and the P-type semiconductor particles and the N-type semiconductor particles form P / N junctions.

3. The large-sized low-power thermoelectric refrigerator with high reliability according to claim 1 or 2, wherein The semiconductor particles and the heat insulation particles are fixedly connected through soldering, the heat insulation particles have tin only on surfaces and no tin in holes during soldering; and the flow guides are connected with the ceramic through epoxy adhesive.

4. The large-sized low-power thermoelectric refrigerator with high reliability according to claim 1 or 2, wherein The heat insulation particles are made of high-strength resin material and have a nickel-tin layer plated on surfaces.

5. The large size, low power thermoelectric refrigerator of good reliability according to claim 1, wherein, The upper ceramic substrate is made of aluminum nitride ceramic.

6. A method for manufacturing a large-size low-power thermoelectric refrigerator with good reliability, applied to the large-size low-power thermoelectric refrigerator with good reliability as claimed in any one of claims 1-5, characterized in that, The method comprises the following steps: S1: manufacturing flow guides, an upper substrate and a lower substrate; S2: printing a layer of tin paste on the upper substrate and the lower substrate, placing semiconductor particles and heat insulation particles on corresponding positions of the lower substrate, and covering the upper substrate; S3: tightly fixing the upper substrate and the lower substrate, and completing a soldering process by using a heating device; S4: cooling and cleaning the soldered product to obtain a thermoelectric refrigerator.

7. The method of claim 6, wherein the method is characterized by a high reliability and a low power consumption of the large-sized thermoelectric refrigerator. The step S1 further comprises: Connecting copper sheets and ceramic sheets through AMB or DBC technology, etching the copper surface to form flow guides with customized shapes, and then cleaning to obtain the substrates.

8. The method of claim 6 or 7, wherein the method is characterized by: The step S2 further comprises: Arranging the semiconductor particles in series between the upper substrate and the lower substrate, soldering the semiconductor particles on the flow guides through soldering to form a refrigeration circuit, and soldering the heat insulation particles on the flow guides through soldering.

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