High quality, large size SiC single crystal material grown by physical vapor deposition

Listened to virtual currency, virtual reality, virtual host... Have you ever heard of virtual growth?

“To grow high-quality silicon carbide (SiC), we need to design, debug and optimize the production process.” The research team led by Chen Xiufang, a professor of state key laboratory of crystal materials, has an important task – growing by physical vapor deposition. High quality, large size SiC single crystal material.

"But the actual growth time, consumption, and energy may be unstable. By computer simulation of the 'virtual growth' process, information such as temperature and growth rate can be known in advance," said Chen Xiufang. This method is just like the "warfare system" and the actual combat in the field.

Recently, the national key research and development plan "medium and low-voltage SiC material devices and their application demonstration in electric vehicle charging equipment" project held a mid-year summary meeting, and the project undertaken by Shandong University and other units won low in only one year. Impurity of 6-inch SiC crystal, the diameter of the single crystal region is more than 15 cm. In order to enable these wafers to be mass-produced, the research team also built a 6-inch SiC single crystal furnace with independent intellectual property rights.

The project leader and professor of Zhejiang University introduced the project. The project will be driven by application requirements and will realize the whole industry chain innovation of material-chip-module-charging equipment-demonstration application. That is to say, high-quality SiC materials and chips will become the core components of charging equipment. Through packaging, design and other processes, electric vehicles are fully and efficiently filled with electric power.

“The project team consists of a number of strong units in the SiC field. Up to now, Project 2 has developed 650V and 1200V SiC MOSFET chips, and Task 3 has developed a cutting-edge high-k gate dielectric technology research and developed The 1700V SiC MOSFET chip, the fourth project completed the trial production of the full SiC half-bridge power module, and the subject five has two charging prototypes in Beijing for trial operation.” Sheng told reporters that the five research groups are like five joints in an industrial chain. Collaboration and mutual support will jointly present the entire chain of SiC from material acquisition to industry landing.

"In the second half of this year, the first issue of the project will be to the supplier of the second and third projects, and the chip packaging and module design will be completed." In the mission document of the grand event, there is a colorful dot plot, time node and task Head-to-head, tail-to-tail, parallel advancement, and sequential completion. The project even developed the “sample delivery plan and standards between the project's upstream and downstream projects”.

"Every time I get together, I am going to solve the problem." Sheng said that the previous year's research is progressing steadily. At this stage, what we need to do is to overcome the core technology and further implement key tasks in a clear direction.

If the whole project is a big ship that is driving to the “new charging method”, the fifth item is the helmsman on the ship. “It clearly proposes the application requirements and achieves the goal, and the R&D team of the upper and middle reaches develops specific promotion plans around the target. Sheng said.

As one of the concrete implementers of the landing, Tyco Tianrun Semiconductor Technology (Beijing) Co., Ltd. Wu Hailei told the Science and Technology Daily reporter that "the new SiC charging module can achieve the highest conversion efficiency of 96% compared with the current charging pile."

The high temperature environment and no-load are the "pain points" of traditional charging piles, and the application of the third generation semiconductor will solve this problem. Wu Hailei said that the research shows that when the working environment temperature of the traditional SiC device charging module reaches 55 °C, the power output is reduced or stopped. The new SiC charging module starts to reduce the power output at 65 °C. "This basically eliminates the summer downtime. Case."

The “Energy Conservation and New Energy Vehicle Industry Development Plan (2012-2020)” shows that by 2020, the cumulative production and sales of pure electric vehicles and plug-in hybrid vehicles will exceed 5 million units. “This means that 4.8 million distributions need to be built. Type charging pile, 12,000 centralized charging and replacing power station." Wu Yalei said. This is a combination of continuous expansion and continuous improvement, a major adjustment of the energy structure and a revolutionary subversion of fossil energy by new energy. Its starting point is the growth of a perfect crystal called SiC, followed by It is an industrial chain with strict layout and innovative surging.