Ferroelectric Polarization Enhancement of Proximity Sensing Performance in Oxide Semiconductor Field-Effect Transistors

Abstract

The explosive development of Internet of Things and wearable electronics greatly promotes the exploitation of diverse sensors in which noncontact proximity sensing is of great significance to perceive diverse information from the environment and human bodies with no need for physical contact. In theory, any long-range interactions can be developed to realize proximity sensing function. In recent years, organic field-effect transistor-based proximity sensors have been realized in which a charged object can be regarded as a gate to modulate transistor’s drain current. However, the low-carrier mobility and shift of threshold voltage in organic transistors limited their sensing performance. Herein, we reported a ferroelectric-polarization-enhanced oxide semiconductor transistor proximity sensor. The polarization state in the ferroelectric layer was well modulated by poling pulse with different widths. Therefore, the optimal operation point of the transistor sensor was precisely controlled by the ferroelectric-polarization-induced shift of the threshold voltage. Such a ferroelectric-modulated oxide semiconductor transistor showed obvious sensing performance to the approach of several common charged objects and presented a much larger current response than that from organic transistor sensors. As an extended application, two transistor sensors were configured to realize the velocity measurement of a charged object.

Thermal Release Transfer of Organic Semiconducting Film for High-Performance Flexible Organic Electronics

“…More details on transistor-based proximity sensing are present in our previous works. 22,62 ■ CONCLUSIONS In summary, we proposed a simple and reliable thermal release transfer method to transfer semiconducting film from a rigid substrate to a flexible one for fabrication of flexible and highperformance organic transistors. DPP-DTT was spin coated on a friction-transferred PTFE template.…”

A Multifunctional Flexible Ferroelectric Transistor Sensor for Electronic Skin

“…[ 2 ] Theoretically, proximity sensing can be realized based on any long‐range interactions, including magnetic, [ 5b ] optical, [ 9,38 ] ultrasound, [ 39 ] and electrostatic [ 17 ] interactions. In recent years, FET proximity sensors are reported by using organic [ 25,40 ] and oxide semiconductors [ 17b ] as active layers. Their proximity sensing mechanism can be briefly described according to Figure a.…”

“…Therefore, E‐skin equipped with proximity sensing function is expected to be used in artificial intelligence, [ 9 ] human–machine interaction, [ 1 ] and robotics. [ 2 ] Theoretically, proximity sensing can be realized based on any long‐range interactions, including magnetic, [ 5b ] optical, [ 9,38 ] ultrasound, [ 39 ] and electrostatic [ 17 ] interactions. In recent years, FET proximity sensors are reported by using organic [ 25,40 ] and oxide semiconductors [ 17b ] as active layers.…”

“…[ 11a ] Especially, in recent years the FET has been developed as sensing devices [ 12 ] to perceive and recognize, e.g., NH 3 and O 2 gases, [ 13 ] DNA, [ 14 ] light, [ 15 ] force, [ 16 ] and charged object. [ 17 ] Furthermore, as one part of E‐skin, FET‐based sensors possess several advantages including excellent electric and mechanical properties, [ 18 ] reduced crosslink between pixels for precise signal distribution mapping, [ 19 ] and less cost compared with complementary metal oxide semiconductor technology. [ 20 ]…”

A Capacitive and Piezoresistive Hybrid Sensor for Long‐Distance Proximity and Wide‐Range Force Detection in Human–Robot Collaboration

“…[ 45 ] Nevertheless, both strategies are mainly confined to either the proximity or contact information, which is not sufficient for the robot control in HRC. Although the robot can feel external objects by optical elements such as fluorescent lamp, light emitting diode (LED), [ 46 ] ferroelectric polarization, [ 47 ] and ultrasonic, [ 48,49 ] it may also result in unavoidable collisions of the sensor because of the low integration between proximity and contact performance. In this scenario, the robot itself is restricted in HRC, much less to the complex and elaborate actions with human.…”