High-Gain Integrated Complementary Inverters Using Doping-Free MoTe2 Transistors

Two-dimensional (2D) semiconductors have been used in pseudo complementary metal-oxide-semiconductor (CMOS) inverters due to their superior transistor performance. However, technological incompatibilities of 2D materials hinder the integration of complementary circuits, resulting in low gain and limited performance. This study presents a simple, doping-free method for integrating a complementary inverter array on a MoTe₂ active layer, enabling seamless integration of both n-type and p-type transistors. The doping-free MoTe₂ complementary inverter array performs robust logical operations with excellent uniformity. The p-type MoTe₂ transistor in the array achieves an impressive switching ratio of >10⁷ and carrier mobility of 22.6 cm²V⁻¹s⁻¹. A maximum high gain of 11 at V_DD = 5 V is achieved for the inverters with SiO₂ as dielectric. Further integration of a hexagonal boron nitride dielectric enhances electrostatic control, resulting in a record-high voltage gain over 300 at V_DD = 4 V. This work not only advances the integration of high-performance logic circuits on 2D materials but also paves the way for future applications in next-generation 2D electronic devices.