According to Xinhua News Agency, Professor Wei Wei of the School of Microelectronics of Fudan University recently, the team of Zhou Peng implemented a subversive two-dimensional semiconductor quasi-non-volatile storage prototype device, which created a third type of storage technology, which is faster than the current U disk. Faster than 10,000 times, the data storage time can also be determined by itself. This solves the difficult problem of “write speed” and “non-volatile” in international semiconductor charge storage technology.
It is understood that there are two main types of semiconductor charge storage technologies. The first type is volatile memory, such as memory in a computer. The data will disappear immediately after a power failure. The second type is non-volatile memory, such as U. Disk, after writing data, no extra energy is needed to save for 10 years. The former can write data in the order of nanoseconds. The second type of charge storage technology requires microseconds to tens of microseconds to save the data.
The new charge storage technology developed this time not only satisfies the writing data speed of 10 nanoseconds, but also realizes the on-demand (10 seconds to 10 years) quasi-non-volatile characteristics of the regulatable data. This new feature Not only in the high-speed memory can greatly reduce the storage power consumption, but also can achieve natural data disappear after the expiration of the data, in a special application scenario to solve the contradiction of confidentiality and transmission.
This research innovatively selected multiple layers of two-dimensional materials to form a semi-floating gate structure transistor: molybdenum disulfide, tungsten diselenide, and germanium disulfide for switching charge transport and storage, respectively, and boron nitride as a tunneling layer. A van der Waals heterojunction of a ladder-valley structure is created. 'Choose these two-dimensional materials will give full play to the rich energy band characteristics of two-dimensional materials. Some of them are just the same door that can be easily switched on and off. The other part is like an airtight wall, and it is difficult for electrons to enter and exit. The regulation of 'write speed' and 'non-volatile' is based on the ratio of these two parts. ' Zhou Peng said.
Write speed is 10,000 times faster than current U disk, data refresh time is 156 times that of memory technology, and it has excellent controllability. It can realize the design of memory structure according to the data effective time requirements... After testing, the researchers found that A new heterojunction based on a full two-dimensional material can achieve a new class III storage characteristic.