Towards an on-chip power supply: Integration of micro energy harvesting and storage techniques for wireless sensor networks
Licentiate thesis, 2019

The lifetime of a power supply in a sensor node of a wireless sensor network is the decisive factor in the longevity of the system. Traditional Li-ion batteries cannot fulfill the demands of sensor networks that require a long operational duration. Thus, we require a solution that produces its own electricity from its surrounding and stores it for future utility. Moreover, as the sensor node architecture is developed on complimentary metal-oxide-semiconductor technology (CMOS), the manufacture of the power supply must be compatible with it. In this thesis, we shall describe the components of an on-chip lifetime power supply that can harvest the vibrational mechanical energy through piezoelectric microcantilevers and store it in a reduced graphene oxide (rGO) based microsupercapacitor, and that is fabricated through CMOS compatible techniques. Our piezoelectric microcantilevers confirm the feasibility of fabricating micro electro- mechanical-systems (MEMS) size two-degree-of-freedom systems which can solve the major issue of small bandwidth of piezoelectric micro-energy harvesters. These devices use a cut-out trapezoidal cantilever beam to enhance the stress on the cantilever’s free end while reducing the gap remarkably between its first two eigenfrequencies in 400 - 500 Hz and 1 - 2 kHz range. The energy from the M-shaped harvesters will be stored in rGO based microsupercapacitors. These microsupercapacitors are manufactured through a fully CMOS compatible, reproducible, and reliable micromachining processes. Furthermore, we have also demonstrated an improvement in their electrochemical performance and yield of fabrication through surface roughening from iron nanoparticles. We have also examined the possibility of integrating these devices into a power management unit to fully realize a lifetime power supply for wireless sensor networks.

Microsuperca- pacitor

On-chip power supply.

Piezoelectric energy harvester

CMOS compatible

MEMS

Kollectorn, MC2
Opponent: Gert Andersson, Rise Acreo

Author

Agin Vyas

Chalmers, Microtechnology and Nanoscience (MC2), Electronics Material and Systems Laboratory

Microelectronic Energy Storage Systems for Integration Alongside Harvesters

Chalmers, 2019-01-01 -- 2020-12-31.

MEMS-baserad energiförsörjning av sensornätverk för Industri - Energy Supply Toolkit

VINNOVA, 2016-11-01 -- 2017-08-24.

Arkitektur för radar med hög uteffekt

VINNOVA, 2017-11-10 -- 2021-05-01.

Driving Forces

Sustainable development

Subject Categories

Electrical Engineering, Electronic Engineering, Information Engineering

Nano Technology

Other Electrical Engineering, Electronic Engineering, Information Engineering

Infrastructure

Nanofabrication Laboratory

Publisher

Chalmers University of Technology

Kollectorn, MC2

Opponent: Gert Andersson, Rise Acreo

More information

Latest update

4/1/2020 1