Si is the most widely used semiconductor material, but it can not break through the bottleneck of high temperature, high power and high frequency. The binary compound semiconductor material GaAs / GaN / SiC has the characteristics of high power density, low energy consumption, high temperature resistance and high luminous efficiency. It can make up for the shortcomings of silicon materials, and has significant advantages in the application fields of radio frequency, power devices, optoelectronics and national defense and military industry.
This paper introduces the technical advantages of GaAs / GaN / SiC and its application in 5g, new energy vehicles and other emerging fields.
1. Compound semiconductors have significant performance advantages and are expected to usher in rapid penetration
1.1 GaAs / GaN / SiC has significant advantages and different application fields
The common semiconductor materials are divided into element semiconductor and compound semiconductor. Elemental semiconductor is a semiconductor material made of single element. There are mainly silicon, germanium, selenium and so on. Compound semiconductor can be divided into binary system, ternary system, multicomponent system and organic compound semiconductor. Binary compound semiconductors have three to five groups (such as gallium arsenide, gallium phosphide, silicon carbide, etc.).
Silicon (SI) is the earliest and most widely used semiconductor material. Germanium (GE) based materials were used in the earliest semiconductor transistors, but they were gradually replaced by Si due to the lack of Ge reserves and difficulty in purification. Silicon has become the most widely used semiconductor material because of its abundant reserves, mature technology and low cost. At present, it is widely used in various discrete devices, integrated circuits, electronic information network engineering and other fields. However, binary compound semiconductor materials have more advantages in high frequency, high temperature, high voltage, optical and other applications.
Binary compound semiconductor material GaAs / GaN / SiC has the characteristics of high power density, low energy consumption, high temperature resistance and high luminous efficiency. It has significant advantages in the application fields of radio frequency, power devices, optoelectronics and national defense and military industry.
GaAs is one of the most important and mature compound semiconductor materials. Compared with Si, GaAs materials have the characteristics of wide band gap and high electron mobility, which can significantly reduce RF size, power consumption and cost advantages. Compared with the new binary compound semiconductor materials such as Gan and SiC, GaAs technology is mature and has obvious cost advantages. GaAs is widely used in RF and optoelectronics.
As a wide band gap semiconductor, Gan is mainly used in microwave radio frequency, power electronics and Optoelectronics due to its high power density, low energy consumption, high frequency and wide bandwidth. Microwave RF direction is mainly 5g communication and satellite communication applications; power electronics includes consumer electronics fast charging, new energy vehicles and other applications; Optoelectronics is mainly in LED and other fields. At present, Gan technology is still in the stage of rapid development, and the cost is relatively high.
Because of its high carrier mobility, high current density, high temperature resistance and high voltage resistance, SiC is often used as power devices. SiC has advantages in the high power field with voltage of 600V and above. Similar to Gan, SiC technology is also in the rapid development stage with relatively high cost.
The application fields of GaAs / GaN / SiC are different. GaAs is the most widely used RF material, which is widely used in radio frequency, wireless communication and special applications. The operating frequency of GaAs applications is mainly within 8GHz, which is suitable for low and medium power devices, such as micro base station and mobile phone RF materials. In addition, as a fast charging material, Gan can significantly reduce the size of the charger and reduce the power consumption. At present, GaN has a rapid penetration in the rapid charging of mobile phones. SiC is an ideal material for power devices, especially in the aspect of high voltage resistance (> 600V), with significant performance advantages, which is widely used in new energy vehicles, power equipment and other fields.
1.2 technology maturity & cost reduction, SiC / GaN is expected to accelerate penetration
SiC / GaN technology has been steadily improved, and the supply of products has been increased rapidly. In the aspect of substrate and epitaxy, 6-inch SiC products have been mass produced, and the research and development of 8-inch substrate has been completed; 4-inch and 6-inch SiC Based Gan epitaxial materials coexist, and the mainstream size of Si based Gan epitaxy is 6-inch. In the future, 6-inch SiC Based Gan and 8-inch Si-based Gan are the main development trends.
According to Casa report, the types of SiC / GaN products sold by various manufacturers in 2019 increased by 60% compared with that in 2017, and 321 new products were added in 2019 alone. SiC Power electronic devices have covered most of the application requirements, and the launch of new power module products has been accelerated, and the number of new modules launched in 2019 accounts for more than half of the total number of new products; the performance of Gan power devices has been gradually improved, and the supply of RF devices has increased.
SiC / GaN device prices continue to decline. Generally speaking, the cost of SiC / GaN devices is still far higher than that of Si products. However, with the progress of technology, the improvement of product yield and the enhancement of scale effect, the price of SiC / GaN devices continues to decline. In terms of power products, take 650V SiC MOSFET as an example, its product price dropped from 3.44 yuan / A in the middle of 2018 to 2.24 yuan / a at the end of 2019. In terms of RF products, the recent price reduction of RF GaN HEMT is even more significant, and the average price at the end of 2019 is nearly 23% lower than that in 2018.
Thanks to the maturity of SiC / GaN devices and the decrease of cost, SiC / GaN devices are expected to accelerate the penetration. Thanks to the improvement of the performance of SiC / GaN power products, it is expected to be widely used in new energy vehicles, fast charging and other markets. According to yole prediction, the market size of SiC and Gan power electronic devices will increase to 1.4 billion US dollars and 370 million US dollars respectively in 2023, and the market penetration rate will reach 3.75% and 1% respectively. Gan RF