Pencirian pertumbuhan lapisan nano grafin di atas elektrod antara digit superkapasitor MEMS

Superkapasitor MEMS khususnya dengan reka bentuk elektrod antara digit (IDE), telah menarik minat pada masa kini dalam bidang seperti bioMEMS, bioperubatan implan, peranti kuasa elektronik dan aplikasi berkuasa tinggi disebabkan kapasiti pengecasannya yang tinggi. Kajian ini membentangkan superkapasitor MEMS dengan lapisan nano grafin tumbuh di atas elektrod. Superkapasitor MEMS terdiri daripada silikon dioksida (SiO2), nikel, grafin, polipirol (Ppy) dan lapisan alkohol polivinil (PVA). Tumpuan diberikan kepada fabrikasi struktur lapisan nano grafin atas elektrod superkapasitor MEMS melalui beberapa proses seperti pemendapan wap kimia secara peningkatan plasma (PECVD), penyejatan alur e dan salutan pusing. Grafin tumbuh melalui proses PECVD selama 10 minit pada kuasa 40 Watt dan pada suhu antara 400°C dan 1000°C. Spektrum Raman menunjukkan puncak pada 1340 dan 1580 cm-1 mewakili jalur D dan G . Puncak 2D wujud dalam julat 2600 - 3000 cm-1. Nisbah bagi keamatan puncak 2D terhadap puncak G pada 1000°C adalah 0.43 menunjukkan kualiti yang baik bagi banyak lapisan grafin

A review: properties of silicon carbide materials in MEMS application

The paper presents the review properties of silicon carbide materials in the MEMS application. The study aims to explore silicon carbide in MEMS technology which considers the development of microscale and integrated devices that combine electronics, electrical and mechanical elements. MEMS has become a key area micro-device technology which incorporates materials, mechanical, electrical, chemical and optical disciplines as well as fluid engineering. The prevalence of MEMS technology in harsh environments has grown tremendously in recent years, especially at high temperatures up to 1240 ̊C, wider bandgap (2.3 – 3.4 eV), a higher breakdown field (30 × 105 V/cm), a higher thermal conductivity (3.2 – 4.9 W/cm- K), a higher saturation velocity (2.5 × 107 cm/s), higher oxidation, corrosive environments and higher radiation. Recent developments in robust MEMS for extreme environments such as MEMS pressure sensors have been widely used in ships, warships, gas turbine engines, cars and biomedical equipment. The growing demand for MEMS pressure sensors with high-temperature operating capabilities, mainly for automotive, gas turbine engine and aerospace applications was investigated from this study as alternative silicon carbide to silicon in the fabrication of these devices

Interdigitated MEMS Supercapacitor for Powering Heart Pacemaker

Power MEMS can be defined as microelectromechanical systems for power generation and energy conversion. Energy harvesting has become an increasingly popular option for powering electronic devices as a long-lasting power source. Energy scavenging is defined as the process by which the energy is derived such as vibration, solar, wind, and thermal. Energy harvesting from the environment can prolong the life cycle and reduce the maintenance costs of electronic devices. Among the various sources of energy storage, Among the various of energy storage, supercapacitor has recently gained much interest in fields such as bioMEMS, biomedical implants and power electronic devices due to its advantages such as high power density, rapid charge and discharge and unlimited number of recharge cycles. In biomedical and bioMEMS systems, an energy storage device is needed to power other active biomedical devices within the system. For implantable devices such as a heart pacemaker, the power requirement is in the range of 30–100 μW. Microsupercapacitors play an important role in energy harvesting system, such as collecting energy from ambient energy sources. Human body is very resourceful in generating micropower in the form of heat dissipation, deformation of elastic tissue, and motion. Due to the advantages of MEMS energy harvesting system, the system can be use widely for biomedical implant devices, such as heart pacemakers and hearing aids, and can be used for a long time and without the need for battery replacement. In this work, planar and double-stacked interdigital electrode supercapacitor designs were modeled using Coventorware software. From simulation, it is observed that for planar structure, the specific capacitance is 0.22 mF/cm−2, and for double-stacked structure specific capacitance can be increased to 0.48 mF/cm−2. In terms of specific power, the planar structure produces 0.99 mW/cm−2, and the double-stacked structure produces 2.18 mW/cm−2. These results highlight the superiority of the double-stacked MEMS interdigital supercapacitor design compared with its planar counterpart in terms of charging capacity and electrical performance, thus making it favorable for powering heart pacemaker

Stress and deformation of optimally shaped silicon microneedles for transdermal drug delivery

In this study, we demonstrated the fabrication of the concave conic shape microneedle with the aid of COMSOL Multiphysics simulation. The stress and buckling of the microneedle structure were simulated by applying various loads ranging from 50 to 800 g perpendiculars to the tip in order to predict the occurrence of microneedles structure deformation. The simulation study indicated that the surface buckling deformation does not occur to the microneedle structure with the increment of the load. The microneedles with dimensions of height and diameter tip ranging from 60 to 100 μm and 1 to 4 μm, respectively had been fabricated via an etching process in a mixture of hydrofluoric acid, nitric acid, and acetic acid. Three optimized microneedles but different in the structures were fabricated via the acidic etching process. The reproducibility of three different microneedle structures was 15, 20, and 60%, respectively. Stress and buckling analyses of the fabricated microneedles were further carried out on the rat skin. The obtained experimental results show promising applications for the deep dermis, stratum corneum to epidermis layer penetration