Review of My Research Work on Ferroelectric Films and Si-Based Device Applications: Opportunity and Challenge

Ferroelectric materials have many interesting physical properties such as ferroelectricity, pyroelectricity, piezoelectricity, and opto-electricity, and applying ferroelectric materials in the forms of thin and thick films and integrating them on the silicon substrate as electronic and MEMS devices is a very attractive research area and challenging. In this paper, we report our research works on ferroelectric MEMS and ferroelectric films for electronic device applications. Pyroelectric thin film infrared sensors have been made, characterized, and a 32×32 array with its size of 1cm×1cm has been obtained on Si membrane. Ferroelectric thin films in amorphous phase have been applied to make silicon based hydrogen gas sensors with the metal/amorphous ferroelectric film/metal device structure, and its turn-on voltage of about 4.5V at ～1000 ppm in air is about 7 times of the best value reported in the literature. For the application of electron emission flat panel display, ferroelectric BST thin films with excess Ti concentrations have been coated on Si tips, the threshold voltage of those ferroelectric film coated tips has been reduced about one order from ～70 V/μm to 4～10 V/μm for different Ti concentrations, and however, the electron emission current density has been increased at least 3～4 order for those coated tips compared to that of the bare Si tips. To fulfill in the thickness gap between thin film of typical ～1 μm made by PVD/CVD and polished ceramic wafer of ～50 μm from the bulk, piezoelectric films with thickness in a range of 1～30 μm have been successfully deposited on Si substrate at a low temperature of 650oC by a novel hybridized deposition technique, and piezoelectric MEMS ultrasonic arrays have been very recently obtained with the sound pressure level up to ～120 dB. More detailed results will be presented and mechanisms will be discussed.

Editorial's note: The Opportunity and Challenge Faced by Molecular Medicine

Since 1980’s,life science has been holding a prominent place in the development ofscience and it is expected to become one of the leading disciplines in the 21 century.Currently the development of life science presents the following characteristics:1.The understanding of life was deepened to the molecule level.

A brand new opportunity and challenge for GEE

Welcome to the second issue of Green Energy&Environment(GEE).The purpose of this Editorial is to give some insight into the opportunities and challenges related to green energy and environment,and to call on more researchers participating actively in and sharing the chance.As is known today,human is currently facing the triple crises:ecological,social and economic,which have

Opportunities and challenges for the development of traditional Chinese medicinenursing under the new healthcare reform

Based on the “Opinions on Deepening the Reform of Medicine and Health”, “Strategic planning outline of thedevelopment of Traditional Chinese Medicine （2016-2030）” and the other relevant polices announced by StateAdministration of Traditional Chinese Medicine of the People’s Republic of China, this paper analyzes and summarizesthe opportunities and challenges for the development of Traditional Chinese Medicine nursing （TCM nursing） under thenew healthcare reform, in order to provide reference and thinking for the professional development of TCM nursing.