Realization of a Graphene/PMMA Acoustic Capacitive Sensor Released by Silicon Dioxide Sacrificial Layer

Xu, Jun; Wood, Graham S.; Mastropaolo, Enrico; Newton, Michael; Cheung, Rebecca

doi:10.1021/acsami.1c05424

Cited by 26 publications

(20 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Theoretically, it is equal to the product between the electrical sensitivity S e and the mechanical sensitivity S m 0 contribution by the equation For this reason, the respective mechanical compliances are indirectly calculated by using eq and eqs , as also described by Baglioni et al . where the input values S e (m V Pa –1 or dB), pretension (N/m), resonance frequency (Hz), the distance membrane–bottom electrode g 0 (m), and V b (V) are obtained from the reported works. ,,,,− For most of the presented data (electrical read-out), the mechanical compliance is indirectly calculated from eq . Thus, Figure may show limitations in the comparison with the results obtained by optical read-out (this work).…”

Section: Resultsmentioning

confidence: 99%

“…Comparison of the mechanical compliance normalized by the area of graphene microphone. The extrapolated mechanical compliances related to the principal graphene microphone works, ,,,,− and the proposed results are presented. The values are normalized by area of the suspended graphene to have an accurate correlation within the different works.…”

Section: Resultsmentioning

confidence: 99%

“…developed an anthracene sublimation assisted process achieving ten layers of CVD graphene suspended over 4 mm openings . Recently, six-layer graphene and 450 nm of PMMA were suspended over a closed cavity by HF vapor release (VHF) of the sacrificial layer after the graphene transfer . The dry release avoids liquids that usually introduce capillary forces that pull down the suspended part introducing ruptures or breaks .…”

Section: Introductionmentioning

confidence: 99%

“…11 Recently, six-layer graphene and 450 nm of PMMA were suspended over a closed cavity by HF vapor release (VHF) of the sacrificial layer after the graphene transfer. 12 The dry release avoids liquids that usually introduce capillary forces that pull down the suspended part introducing ruptures or breaks. 13 Moreover, exposing the graphene to wet HF might also lead to unwanted delamination of the graphene from the substrate.…”

Section: ■ Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Sensitive Transfer-Free Wafer-Scale Graphene Microphones

Pezone

Baglioni

Sarro

et al. 2022

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

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 breakthrough device concepts, geometries, and materials. Graphene is an attractive material for enabling these breakthroughs due to its flexibility, strength, nanometer thinness, and high electrical conductivity. Here, we demonstrate that transfer-free 7 nm thick multilayer graphene (MLGr) membranes with diameters ranging from 85− 155 to 300 μm can be used to detect sound and show a mechanical compliance up to 92 nm Pa −1 , thus outperforming commercially available MEMS microphones of 950 μm with compliances around 3 nm Pa −1 . The feasibility of realizing larger membranes with diameters of 300 μm and even higher compliances is shown, although these have lower yields. We present a process for locally growing graphene on a silicon wafer and realizing suspended membranes of patterned graphene across through-silicon holes by bulk micromachining and sacrificial layer etching, such that no transfer is required. This transfer-free method results in a 100% yield for membranes with diameters up to 155 μm on 132 fabricated drums. The device-to-device variations in the mechanical compliance in the audible range (20−20000 Hz) are significantly smaller than those in transferred membranes. With this work, we demonstrate a transfer-free method for realizing wafer-scale multilayer graphene membranes that is compatible with high-volume manufacturing. Thus, limitations of transfer-based methods for graphene microphone fabrication such as polymer contamination, crack formation, wrinkling, folding, delamination, and low-tension reproducibility are largely circumvented, setting a significant step on the route toward high-volume production of graphene microphones.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: ■ Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Sensitive Transfer-Free Wafer-Scale Graphene Microphones

Pezone

Baglioni

Sarro

et al. 2022

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

show abstract

“…21–25 In general, these works focused on fabricating a condenser microphone structure, involving either wet or dry transfer 20–22 of large graphene membranes (from 2 to 12 mm in diameter) over pre-patterned substrates or via dry etching of a sacrificial layer. 23 In these devices, the incoming sound is transduced to an electrical signal via the change in capacitance between a fixed backplate and the movable membrane. Although these works have demonstrated successful capacitive readout of audio signals with high output voltage per unit pressure, other important device performance parameters, like the mechanical sensitivity, the signal-to-noise ratio (SNR), total harmonic distortion (THD), bandwidth and dynamic range, have been less extensively characterized.…”

Section: Introductionmentioning

confidence: 99%

Ultra-sensitive graphene membranes for microphone applications

et al. 2023

View full text Add to dashboard Cite

show abstract

A Review of Acoustic Devices Based on Suspended 2D Materials and Their Composites

Wan,

Liu,

Zheng

et al. 2023

Adv Funct Materials

View full text Add to dashboard Cite

Acoustic devices play an increasingly important role in modern society for information technology and intelligent systems, and recently significant progress has been made in the development of communication, sensing, and energy transduction applications. However, conventional material systems, such as polymers, metals and silicon, show limitations to fulfill the evolving requirements for high‐performance acoustic devices of small size, low power consumption, and multifunctional capabilities. 2D materials hold the promise in overcoming the development bottleneck of acoustic devices aforementioned, given their atomic‐thin thickness, extensive surface area, superior physical properties, and remarkable layer‐stacking tunability. By suspending the 2D materials, mechanical and thermal disruption from substrate will be eliminated, which will enable the development of new classes of acoustic devices with unprecedented sensitivity and accuracy. In this review, the recent progress of acoustic devices based on suspended 2D materials and their composites, especially applications in the audio frequency, static pressure, and ultrasonic frequency range, is briefly summarized, emphasizing the advantageous properties of suspended 2D materials and related outstanding device performance. Together with the development of 2D membrane synthesis, transfer, as well as microelectromechanical fabrication process, suspended 2D materials will shed light on the next‐generation high‐performance acoustic devices.

show abstract

Realization of a Graphene/PMMA Acoustic Capacitive Sensor Released by Silicon Dioxide Sacrificial Layer

Cited by 26 publications

References 26 publications

Sensitive Transfer-Free Wafer-Scale Graphene Microphones

Sensitive Transfer-Free Wafer-Scale Graphene Microphones

Ultra-sensitive graphene membranes for microphone applications

A Review of Acoustic Devices Based on Suspended 2D Materials and Their Composites

Contact Info

Product

Resources

About