Piezoelectric
Ceramics
Dr. & Prof. Chun-Huy Wang
Electronic Engineering
Nan-Jeon Institute of Technology
Tainan, Taiwan
OUTLINE
Introduction
Electronic Ceramics
Piezoelectricity
Piezoelectric Ceramics
Fabrication Process of Piezoelectric
Ceramics
Piezoelectric Ceramics: Applications
＜Electronic Ceramics ＞
Dielectric
Piezoelectric
Pyroelectric
Ferroelectric
Dielectric Property
Piezoelectricity
Pyroelectricity
Ferroelectricity
Piezoelectricity
Mechanical and electrical energy conversion
phenomena, discovered by France Scientist
Pierre and Jacques Curie brother in
1880.
Direct Piezoelectric Effect
Mechanical
Electrical
Converse Piezoelectric Effect
Piezoelectric Ceramics
The famous one is the lead zirconium titanium,
Pb(Zr,Ti)O3 [abbrev. as PZT].
PZT was first reported as ferroelectric materials in
1950 by Shirane et al., and reported as a useful
piezoelectric materials by Jaffe et al. in 1954.
Below the Curie temperature, PZT ceramics is
ferroelectrics with piezoelectricity, and it was
paraelectrics without piezoelectricity at the
temperature higher than Curie Temperature.
Piezoelectric Ceramics
 The
crystal structure of most traditional
piezoelectric ceramics are pervoskite structure,
with the chemical formula as ABO3.
 A is a larger divalent metal ions, usually
lead(Pb) or barium(Ba). Located at the corner
of the cubic.
 B is a smaller trivalent metal ions, usually
titanium(Ti) or zirconium(Zr). Located at the
center of the cubic.
 O is oxygen ion. Located at the center of the
faces.
Piezoelectric Ceramics
 (perovskite)結構，化學式為
cornal
center
face
center
Pervoskite structure, with the chemical
formula as ABO3 e.g. : BaTiO3
Piezoelectric
Ceramics
Piezoelectric Ceramics
For a three-dimensional
unit cell, there are six
possible directions to
displace the central positive
ion towards the face
centered negative ions.
 Therefore, there are six
different choices for
spontaneous polarization in
the ferroelectric phase,
Piezoelectric Ceramics
Piezoelectric Ceramics
Fabrication Process of Piezoelectric Ceramics
K2CO3、Nb2O5、TiO2、Bi2O3、Na2CO3
(1-x)(Na0.5K0.5)NbO3-x Bi0.5(Na0.93K0.07)0.5TiO3
Weighting according to formula
x varied from0.02、
0.04、 0.06、0.08、
0.10
Ball mill to mix
Ceramics prepared
by conventional
mixed oxide
method
Drying & Grinding powder
Calcining 950℃/4h
12
Next page
Previous page
Polymer
binder
Ball-Mill to grind
Form to near finished Ddiameter=15mm
Remove binder
Surface
grind
t=1mm
Sintering 1100℃ 3~7 h
Measuring
Density
SEM、XRD
Silver paste on electrodes
Measuring C1KHz、D1KHz
Poling 100℃~250℃ 4 kV/30min
fr、R、fa 、C1KHz、D1KHz
kp、kt、K33T
13
Fabrication Process of
Piezoelectric Ceramics
Sintering and poling are two important key
fabrication processes related to the microstructure
of the PZT ceramics.
The sintering process gives the grain structure for
the ceramics and the poling process gives the
piezoelectric effects for the ceramics.
The final grain size and the perfect crystal
formation depend on the temperature and time of
the sintering process.
Domain and domain boundaries of
polycrystalline BaTiO3
(left)domain structure of unpoled ferroelectric ceramics
(right) graphical representation
Poling
Poling is the final process in the
fabrication. Initially, unpoled ceramics
have no piezoelectricity because the
piezoelectric tensors of the grains are
randomly oriented.
During the poling process, ferroelectric
switching occurs and creates non zero
overall piezoelectric tensors.
Poling
(left)unpoled, (center)during poling, (right)after poling
P~E Curve
P-E curve vs Voltage Applied
壓電陶瓷材料應用之分類
壓電陶瓷按照應用分類共分爲七大類：
一、 壓電振盪及材料
二、 壓電聲電元件：蜂鳴器、送話器、受話器、壓電喇叭
三、 壓電超音波換能器：超音波清洗、超音波霧化、超音
波美容、超音波探測
四、 資訊處理元件：濾波器、諧振器、檢波器、監頻器、
表面聲波、延遲線
五、 動力裝置：點火器、超音波切割、超音波粘接、壓電
馬達、壓電變壓器
六、 壓電感測器：速度、加速度計、角速度計、微位移器
七、 光電元件：光調節器、光調節閥、光電顯示、光資訊
儲存、影象儲存和顯示
Ceramics Resonator
Resonator is the basic frequency control
component, the piezoelectric filter is
composed by the piezoelectric resonator .
Ceramics Resonator
Ceramic Filter
Monolithic Filter (used for low frequency)
SAW Resonator and Filter
表面聲波(surface acoustic wave，簡稱SAW)是在1885年
由英國物理學家Lord Rayleigh所發現，故亦稱為
Rayleigh波，初期主要應用在地震學方面的研究。
Rayleigh波是由一個壓縮波及一個剪向波相耦合而成，
若表面聲波在壓電基板上傳播，則會在基板上產生相對
應的時變電場。
SAW Resonator and Filter
In natural world, SAW can
create by earthquake.
In engineering, SAW can create
by piezoelectric effect.
SAW Resonator and Filter
SAW Resonator and Filter
One Port Resonator
SAW Resonator and Filter
Two Port Resonator
SAW Resonator and Filter
Applications of SAW Resonator
振盪子產品應用實例
霧化振盪子用於加濕機、
精油霧化以及醫療霧化
領域
超音波加濕器
超音波加濕技術具有加濕效率高、電耗低、穩
定性好、安全性高的特點，可以實現溫度控制
與濕度控制的相互獨立、互不干擾。
振盪子產品應用實例
美容復健用超音
波按摩頭
空中換能器應用實例
• 汽車倒車雷達
致動器
螺旋式
致動器應用:
微形馬達,
手機,
數位相機
致動器應用於相機鏡頭模組
壓電陶瓷變壓器的應用
筆記型電腦、數位相機
壓
電
液
示晶
器顯
識別路標地圖、手機
陶
液晶TV、測定器及
其它
瓷
變
壓
器
家庭影院、
遊戲機
壓低
電電
源流
高
空氣清淨
機
傳真
機
影印機
單層壓電變壓器應用實例

單層式壓電變壓器：用於臭氧產生器、 負離子產生
器、 靜電消除裝置、電子口罩等等高壓產生單元模
組
積層壓電變壓器應用實例

積層式壓電變壓器：用於筆記型電腦液晶顯示器、
桌上型電腦液晶顯示器、個人數位助理(PDA)、數
位相機(DSC)、數位攝影機(DSC)之冷陰極管電源
模組等。
蜂鳴器
外激式壓電
蜂鳴器
自激式壓電
蜂鳴器
壓電蜂鳴片
回饋式蜂鳴
片
•蜂鳴器的作用 蜂鳴器是一種一體化結構 的
電子訊響器，採用直流電壓供電，廣氾應 用
於計算機、印表機、影印機、報警器、電 子
玩具、汽車電子設備、電話、定時器等電 子
產品中作發聲元件。
壓電式平面喇叭
• 經由雙簧式壓電致動器出力使基板產生振動從而
構成一揚聲機制：用於行動電話、個人數位助理
(PDA) 、筆記型電腦等之發聲模組
Distributed Mode Actuator (DMA)
Harvesting Energy Application
Energy harvesting (also known as
Power harvesting or energy scavenging)
is the process by which energy is derived
from external sources (eg solar power,
thermal energy, wind energy, salinity
gradients and kinetic energy), captured
and stored.
Power Platform
2007年兩位MIT的學生提出在都市區域
內建立壓電地板的觀念[source:
Christian Science Monitor]，他們的構想
是在鬧區例如火車站、購物商場建立
壓電地板來利用人們行走的步伐所產
生的機械能轉換成為電能。雖然人們
每一步所產生的電力非常小約只能點
亮兩個60W燈泡一秒鐘，但如果有很多
人在行走則可以產生相當大的能量。
Power Platform
2008年以色列的Innowattech公司開
始利用所生產的IPEG (Innowattech
Piezoelectric Power Generator)發電
器來試驗建構壓電道路
Power Platform
2010年
Innowattech公司再與以色列國
家道路公司(Israel National Road
Company，INRC)合作建構壓電鐵路。
Power Platform
 日本東日本鐵路公司(East
Japan Railway
Company，JR East)在2008年初在東京車站的
收票口建立壓電地板，利用此一地板來產生發
電，到目前每天發的電力為1,400kW/sec。
Harvesting Energy Application
Most piezoelectric electricity sources
produce power on the order of
milliwatts, too small for system
application, but enough for hand-held
devices.
Piezoelectric generators are suitable
for power industrial wireless sensor
applications.
Thank you！