High-performance wafer-scale transfer-free graphene microphones

A repeatable method to fabricate multi-layer graphene (ML-gr) membranes of 2r = 85 - 155 μm (t < 10 nm) with a 100% yield on 100 mm wafers is demonstrated. These membranes show higher sensitivity than a commercial MEMS-Mic combined with an area reduction of 10x. The process overcomes one of the main limitations when integrating graphene...

Wafer-Scale Fabrication of Graphene-Based Condenser Microphones

The evolution of microphone technology can be linked to the growing multimedia and communication market. The first is linked to the music and audiovisual industry, while the latter is linked to smartphones, smart mobility, and home automation. In all of these audio applications, the common trend is toward downsizing and performance improvement....

Humidity sensor based on multi-layer graphene (MLG) integrated onto a micro-hotplate (MHP)

This work demonstrates a humidity sensor based on two multi-layered graphene (MLG) strips monolithically integrated onto a micro-hotplate (MHP). A transfer-free approach was adopted to release the graphene from the catalyst to reduce device variations and ensure scalability. The sensing performance of the device was tested by exposing the device...

Sensitive Transfer-Free Wafer-Scale Graphene Microphones

During the past decades micro-electromechanical microphones have largely taken over the market for portable devices, being produced in volumes of billions yearly. Because performance of current devices is near the physical limits, further miniaturization and improvement of microphones for mobile devices poses a major challenge that requires...

Wafer-scale transfer-free process of multi-layered graphene grown by chemical vapor deposition

Chemical vapour deposition (CVD) has emerged as the dominant technique to combine high quality with large scale production of graphene. The key challenge for CVD graphene remains the transfer of the film from the growth substrate to the target substrate while preserving the quality of the material. Avoiding the transfer process of single or...

Low Temperature CVD Grown Graphene for Highly Selective Gas Sensors Working under Ambient Conditions

In this paper we report on gas sensors based on graphene grown by Chemical Vapor Deposition at 850 °C. Mo was used as catalyst for graphene nucleation. Resistors were directly designed on pre-patterned Mo using the transfer-free process we recently developed, thus avoiding films damage during the transfer to the target substrate. Devices...

CVD transfer-free graphene for sensing applications

The sp² carbon-based allotropes have been extensively exploited for the realization of gas sensors in the recent years because of their high conductivity and large specific surface area. A study on graphene that was synthetized by means of a novel transfer-free fabrication approach and is employed as sensing material is herein...

An innovative approach to overcome saturation and recovery issues of CVD graphene-based gas sensors

<br/>In this work, we present an innovative method which enables to solve fundamental limitations affecting graphene-based chemi-sensors operating under environmental conditions, namely the lack of signal saturation and the scarce recovery after the detection step. The method, which exploits the differential current instead of the current itself...

High sensitive gas sensors realized by a transfer-free process of CVD graphene

The work herein presented investigates the behavior of graphene-based gas sensors realized by using an innovative way to prepare graphene. The sensing layer was directly grown by chemical vapor deposition on pre-patterned CMOS compatible Mo catalyst and then it was eased on the underlying SiO2 through a completely transfer-free process. Devices...