Materials

Flexible Single‐Substrate Integrated Active‐Matrix Pyroelectric Sensor

Abstract:

Recently developed flexible active matrix sensors employ organic and large area electronics to enable artificial sensing skin applications. In the proof‐of‐concept presented here, an active matrix proximity sensor‐array is formed by monolithic integration of screen‐printed sensors with organic transistors on a single sheet of a polymer film, using only seven industrially scalable patterning steps. A ferroelectric co‐polymer of polyvinylidendifluoride (PVDF) serves as the pyro‐sensor material, and bottom‐gate top‐contact organic thin film transistors switch the sensors during operation. An on/off ratio well above 103 and a low off‐current below 8 × 10−11 A of the organic transistors result in a dynamic range of 44 dB and allow to detect a human hand approaching to a distance of 20 cm with a signal‐to‐noise ratio of 28 dB. A basic matrix operation is demonstrated by the correct tracking of a moving human hand.