@misc{StrobelAlvaradoChavarinKnautetal., author = {Strobel, Carsten and Alvarado Chavarin, Carlos and Knaut, Martin and V{\"o}lkel, Sandra and Albert, Matthias and Hiess, Andre and Max, Benjamin and Wenger, Christian and Kirchner, Robert and Mikolajick, Thomas}, title = {High Gain Graphene Based Hot Electron Transistor with Record High Saturated Output Current Density}, series = {Advanced Electronic Materials}, volume = {10}, journal = {Advanced Electronic Materials}, number = {2}, issn = {2199-160X}, doi = {10.1002/aelm.202300624}, abstract = {Hot electron transistors (HETs) represent an exciting frontier in semiconductor technology, holding the promise of high-speed and high-frequency electronics. With the exploration of two-dimensional materials such as graphene and new device architectures, HETs are poised to revolutionize the landscape of modern electronics. This study highlights a novel HET structure with a record output current density of 800 A/cm² and a high current gain α, fabricated using a scalable fabrication approach. The HET structure comprises two-dimensional hexagonal boron nitride (hBN) and graphene layers wet transferred to a germanium substrate. The combination of these materials results in exceptional performance, particularly in terms of the highly saturated output current density. The scalable fabrication scheme used to produce the HET opens up opportunities for large-scale manufacturing. This breakthrough in HET technology holds promise for advanced electronic applications, offering high current capabilities in a practical and manufacturable device.}, language = {en} } @misc{StrobelAlvaradoChavarinRichteretal., author = {Strobel, Carsten and Alvarado Chavarin, Carlos and Richter, Karola and Knaut, Martin and Reif, Johanna and Völkel, Sandra and Jahn, Andreas and Albert, Matthias and Wenger, Christian and Kirchner, Robert and Bartha, Johann Wolfgang and Mikolajick, Thomas}, title = {Novel Graphene Adjustable-Barrier Transistor with Ultra-High Current Gain}, series = {ACS Applied Materials \& Interfaces}, volume = {14}, journal = {ACS Applied Materials \& Interfaces}, number = {34}, issn = {1944-8244}, doi = {10.1021/acsami.2c10634}, pages = {39249 -- 39254}, abstract = {A graphene-based three terminal barristor device was proposed to overcome the low on/off ratios and insufficient current saturation of conventional graphene field effect transistors. In this study, we fabricated and analyzed a novel graphene-based transistor, which resembles the structure of the barristor but uses a different operating condition. This new device, termed graphene adjustable-barriers transistor (GABT), utilizes a semiconductor-based gate rather than a metal-insulator gate structure to modulate the device currents. The key feature of the device is the two graphene-semiconductor Schottky barriers with different heights that are controlled simultaneously by the gate voltage. Due to the asymmetry of the barriers, the drain current exceeds the gate current by several orders of magnitude. Thus, the GABT can be considered an amplifier with an alterable current gain. In this work, a silicon-graphene-germanium GABT with an ultra-high current gain (ID/IG up to 8 × 106) was fabricated, and the device functionality was demonstrated. Additionally, a capacitance model is applied to predict the theoretical device performance resulting in an on-off ratio above 106, a swing of 87 mV/dec, and a drivecurrent of about 1 × 106 A/cm2.}, language = {en} }