Semiconductor refrigeration cooling technology

      With the continuous pursuit of human computing power, more and more transistors are inserted into the computing chip. The density of each computing unit is increasing. At the same time, higher frequency also brings higher working voltage and power consumption to the chip. It can be predicted that in the next few years, we will continue to pursue to improve the computing performance of the chip, which also means that we also need to continuously solve the heat dissipation problem of chip temperature.

       Semiconductor refrigeration cooling technology based on the principle of thermoelectric effect is a new cooling method with high controllability, simple use and low cost. It has been gradually used in the field of heat dissipation.

     Thermoelectric effect is a direct conversion of voltage generated by temperature difference, and vice versa. Simply put a thermoelectric device, when there is a temperature difference between their two ends, it will produce a voltage, and when a voltage is applied to it, it will also produce a temperature difference. This effect can be used to generate electrical energy, measure temperature, and cool or heat objects. Because the direction of heating or cooling depends on the applied voltage, thermoelectric devices make temperature control very easy.

     Compared with traditional air cooling and liquid cooling, semiconductor refrigeration chip cooling  has the following advantages: 1 The temperature can be reduced below room temperature; 

2. Accurate temperature control (using closed-loop temperature control circuit, the accuracy can reach ± 0.1 ℃); 

3. High reliability (refrigeration components are solid devices without moving parts, with a service life of more than 200000 hours and low failure rate); 

4. No working noise.

TE cooling challenge：

1. At present, the refrigeration coefficient of semiconductor is small, and the energy consumed during refrigeration is much greater than the refrigeration capacity. The energy consumption ratio of Tec radiator is too low, and Tec radiator cannot become the mainstream cooling solution at this stage.

2. When the TEC refrigeration blade is working, it needs effective heat dissipation at the hot end while cooling at the cold end. That is to say, if the TEC refrigeration device wants to carry out high-power refrigeration and output to the CPU for heat dissipation, it also needs to be continuously dissipated, resulting in the inability of high-power tec to work independently.

3. The moisture in the air is easy to form condensation in the parts below the room temperature in the face of the large temperature difference environment manufactured by tec. It is necessary to design a certain sealing environment around the processor to avoid the risk of condensation and damage to the main board components.

        With the improvement of the process, the transistor density increases, and the package die area of the CPU core becomes smaller and smaller. According to the principle of thermodynamics, when the heat conduction area is smaller, a larger temperature difference is needed to maintain the heat conduction performance. The traditional heat dissipation form with smaller temperature difference can not solve this problem. Even if the CPU power consumption is not high, it will still seriously accumulate heat, resulting in too low frequency limit. Tec naturally has a large temperature difference attribute (the temperature at the heat absorption end can easily reach - 20 ℃), which may be the best solution to solve the problem of small area and high heat conduction.