Graphene for electronics applications with Lilei Ye

Lilei Ye is the business developer for electronics applications for the Graphene Flagship. She has more than 10 years of experience on carbon-based materials development on electronics. Lilei has been involved in technical project management interfacing between academia and industry with business development, product development and technology transfer. She now offers her thoughts on the current state of graphene for applications in the field of electronics.

What is the current state of graphene for electronics applications?

Electronics is an important application area for graphene and related 2D materials. In the early days the vision for graphene electronics was to replace silicon technology. However, it is now widely accepted that graphene will be integrated on already existing CMOS technologies. In enhanced silicon technologies, Europe has a good position in the global scenario, having a few important companies in the sector, as well as the technical/academic knowledge.

Several focus subareas have been identified as having high potential for Europe, based on the market potential and on the current technological potential. In the area of electronics, the subareas of sensor applications (pressure sensor, magnetic sensor, gas and chemical sensor, image sensor and biomedical sensor) have been identified as having highest potential. Flexible high frequency devices, mechanical terahertz modulators, graphene radio frequency transistors and functionalized graphene photodetectors have also been identified to have some market and technological potential. One more direction is graphene-based transparent electrodes, touch screens, and flexible and wearable devices are also developed to handle the shortages of existing materials. All these subareas represent good opportunities for Europe, either because companies/industries can be enabled by graphene development or because a good part of the corresponding value chain is already in Europe, and in many cases world class research is supporting the creation of new products.

What challenges does graphene face in becoming integrated in electronics?

For many application areas, several challenges were already identified, such as quality, repeatability, reliability, production cost and wafer scale integration are common to many of the application areas. However, a few are also specific to electronics applications:

• Compatibility to existing process and manufacturing techniques, especially for all wafer scale applications
• Competition with existing mature semiconductor systems, which are very conservative
• Technical difficulty: growth, transfer, contact resistance, and so on
• Patent thicket from large companies, protecting a large part of the landscape

For many of the applications, the wafer scale integration of graphene and potentially other 2D materials is required for products to appear on the market. This process will be accelerated by the developments of the Experimental Pilot Line planned by the Graphene Flagship, which is dedicated to the wafer-scale integration process. Products not depending on wafer scale integration of graphene, such as flexible (printed) sensors and thermal material on the packaging level, are expected to appear first, in the next five years. Others that depend on it will take a longer time: pilot production is expected at the earliest in 2025.

The lack of standards is also a well-known problem with graphene. Only after the standard is defined, accepted, and used by both the producers and the users will the large-scale usage of graphene be truly possible.

What are the most promising graphene electronics products currently on the market?

In the area of electronics, it is expected that graphene will first complement and enhance silicon technology based on a complementary metal–oxide–semiconductor (CMOS) process. Some companies (TeamGroup and Huawei) have applied graphene-based sheet as a heat dissipation material for computer and mobile phone cooling. Versarien, a Graphene Flagship partner, has improved the diaphragm structures in earphones by adding graphene flakes to enhance sound quality. Even though these products are not directly related to electronic devices, they are indirectly associated with electronic applications.