Flexible High Voltage Thin Film Transistor for Self-powered Wearable Electronics

f-HVTFT mounted on a platform for bending test

Invention Summary:

Wearable systems have been emerging for broad applications. One of the major technical challenges for the technology is its power management. The self-powered wearable electronics which aim to provide users continuous, non-interrupted, and hassle-free experiences are highly desired. However, current self-powered technology faces 3 challenges: (1) unstable due to the environment variations; (2) requirement of an external bulky power management component, and (3) built on the rigid substrate.

To address these issues, a research team led by Professor Yicheng Lu at Rutgers University has developed flexible high voltage thin film transistors (f-HVTFT). This novel f-HVTFT is designed with a unique structure to achieve uniform field distribution with better mechanical strength and electrical characteristics against bending along any directions, which is particularly important for wearable systems. The f-HVTFT is fabricated at low temperature. The high blocking voltage (~150V) and sufficient on-current (~10 micro-A) satisfy the output characteristics of different energy sources, such as wearable triboelectric nanogenerators (WTNG) of high impedance and wearable solar cells. The small off-current (~ 0.01 pA) promises the low standby power, which is desired in wearable system applications. The f-HVTFT opens the possibility of a lightweight, integrated and wearable power management system.

By integrating power management system with multiple wearable energy sources, a more stable power can be provided for wearable electronics without external connections. It enables stable and sustainable operation of wearable and portable systems.

Market Applications:

  • Self-powered wearable systems built on flexible substrates, including plastics and fabrics
  • Flexible power management systems with small size, lightweight, and stable and sustainable operation
  • Flexible HVTFTs for inverter and converter circuits used in MEMS and flexible displays


  • High voltage operation, key for power management
  • Flexible – suitable for wearable systems
  • Low temperature processing (<400oC)
  • More reliable and stable than organic HVTFT
  • Mechanical strength and uniform electrical characteristics against bending along random directions
  • Low cost

Intellectual Property & Development Status:

Patent pending. Available for licensing and/or research collaboration.

Patent Information:
Lisa Lyu
Assistant Director
Rutgers, The State University of New Jersey
Flexible electronics