Development of Strain-controlled Multi-Graphene-Nanoribbons-Base Dumbbell-Shape Photovoltaic Devices

在过去的一年里，研究计划中设定的里程碑已经实现，并在学术期刊上发表。已经建立了用于制造带宽度小于70 nm的石墨烯纳米颗粒（GNR）结构的高度可重复、稳定和可靠的制造工艺。使用这种工艺方法，可以在具有稳定电子性能的器件上图案化和结构化宽度为30 nm的GNR。在太阳模拟器和从激光束聚焦的两种不同波长的光下测试了该器件的光子特性。当在532 nm的光束下进行测试时，该器件的光子响应率为5.5x10^3（A/W），与当前文献中的几种石墨烯和GNR基器件相当，甚至更大。其次，通过施加机械应力来控制和进一步增强石墨烯纳米带的电子能带性质的概念也得到了实验测试和验证。数据显示，在机械应变下，应变计的应变系数高达1,500，比几种金属应变计都要大。本研究所验证的概念，证明GNR结构应用于高性能半导体器件的可行性。这些数据已发表在高排名的学术期刊上，并在日本和葡萄牙的两个国际会议上发表。此外，在日本发表的论文获得了IEEE EPS日本分会奖。

In the previous year, the milestones set in the research plan has been acheived and published in academic journals. A highly repeatable, stable, and a reliable fabrication process for fabricating graphene nanoribbon(GNR) structures of ribbon width less than 70-nm has been established. Using this process methodology, GNR of width 30-nm can be patterned and structured on a device with stable electronic performance. The photonic properties of this device was tested under a solar simulator and two different wavelength of lights focused from a laser beam. When tested under a light beam of 532-nm, the device responded with a photonic responsivity of 5.5x10^3 (A/W) which is comparable and even larger than several graphene and GNR based devices in current literature. Secondly, the concept of controlling and further enhancing the electronic band properties of graphene nanoribbons by applied mechanical stress has also been tested and validated experimentally. The data showed a very high gauge factor of 1,500 under mechanical strain, which is also exceptionally larger than several metallic strain gauges. The concepts tested and validated in this research proves the feasibility of GNR structures application to high performing semiconductor devices. The data has been published in highly ranked academic journals and presented in two international conferences, in Japan and Portugal. In addition, the paper presented in Japan has received IEEE EPS Japan Chapter Award.