红外与激光工程
紅外與激光工程
홍외여격광공정
INFRARED AND LASER ENGINEERING
2009年
6期
961-965,1019
,共6页
孟祥建%韩莉%孙璟兰%褚君浩
孟祥建%韓莉%孫璟蘭%褚君浩
맹상건%한리%손경란%저군호
铁电%热释电%弛豫铁电体%自极化
鐵電%熱釋電%弛豫鐵電體%自極化
철전%열석전%이예철전체%자겁화
Ferroelectricity%Pyroelectricity%Relaxor ferroelectrics%Self-polarization
采用sol-gel方法在Pt/Ti/SiO_2/Si衬底上制备了0.7Pb(Mg_(1/3)Nb_(2/3))O_3-0.3PbTiO_3,并研究了其铁电和热释电性质.X射线衍射结果表明薄膜具有高度的(111)择优取向.结果显示,在没有任何极化处理情况下,薄膜具有稳定的热释电系数,达到1.58×10~(-8) Ccm~(-2)K~(-1).当极化电场高于3倍薄膜的矫顽电场时,薄膜的热释电系数几乎保持不变.撤掉极化电场后,薄膜的热释电系数在10天后仅仅衰减4%左右,远比PZT薄膜稳定.研究发现不同方向极化处理,薄膜的热释电电流具有非对称性,即正向极化时热释电电流随电场增加而增大,负方向极化处理时,热释电电流随电场增加而减小.这些结果显示0.7Pb(Mg_(1/3)Nb_(2/3))O_3-0.3PbTiO_3表现出的优异热释电特性起源于薄膜中的自极化效应.
採用sol-gel方法在Pt/Ti/SiO_2/Si襯底上製備瞭0.7Pb(Mg_(1/3)Nb_(2/3))O_3-0.3PbTiO_3,併研究瞭其鐵電和熱釋電性質.X射線衍射結果錶明薄膜具有高度的(111)擇優取嚮.結果顯示,在沒有任何極化處理情況下,薄膜具有穩定的熱釋電繫數,達到1.58×10~(-8) Ccm~(-2)K~(-1).噹極化電場高于3倍薄膜的矯頑電場時,薄膜的熱釋電繫數幾乎保持不變.撤掉極化電場後,薄膜的熱釋電繫數在10天後僅僅衰減4%左右,遠比PZT薄膜穩定.研究髮現不同方嚮極化處理,薄膜的熱釋電電流具有非對稱性,即正嚮極化時熱釋電電流隨電場增加而增大,負方嚮極化處理時,熱釋電電流隨電場增加而減小.這些結果顯示0.7Pb(Mg_(1/3)Nb_(2/3))O_3-0.3PbTiO_3錶現齣的優異熱釋電特性起源于薄膜中的自極化效應.
채용sol-gel방법재Pt/Ti/SiO_2/Si츤저상제비료0.7Pb(Mg_(1/3)Nb_(2/3))O_3-0.3PbTiO_3,병연구료기철전화열석전성질.X사선연사결과표명박막구유고도적(111)택우취향.결과현시,재몰유임하겁화처리정황하,박막구유은정적열석전계수,체도1.58×10~(-8) Ccm~(-2)K~(-1).당겁화전장고우3배박막적교완전장시,박막적열석전계수궤호보지불변.철도겁화전장후,박막적열석전계수재10천후부부쇠감4%좌우,원비PZT박막은정.연구발현불동방향겁화처리,박막적열석전전류구유비대칭성,즉정향겁화시열석전전류수전장증가이증대,부방향겁화처리시,열석전전류수전장증가이감소.저사결과현시0.7Pb(Mg_(1/3)Nb_(2/3))O_3-0.3PbTiO_3표현출적우이열석전특성기원우박막중적자겁화효응.
Ferroelectric and pyroelectric properties of 0.7Pb(Mg_(1/3)Nb_(2/3))O_3-0.3PbTiO_3 thin fill deposited on Pt/Ti/SiO_2/Si substrates using a sol-gel method were investigated. X-ray diffraction results showed that the fills were highly (111) oriented. It was found that the films show a stable pyroelectric coefficient (1.58×10~(-8) Ccm~(-2)K~(-1)) without any poling processes. Nearly constant pyroelectric coefficient was obtained when the applied poling dc bias field increased to greater than three times of its coercive field. The pyroelectric coefficient of the poled 0.7Pb(Mg_(1/3)Nb_(2/3))O_(3)-0.3PbTiO_3 thin film capacitor dropped to 96% of its initial value after ten days, which was much more stable than that of PZT samples. Asymmetric pyroelectric currents were found in the 0.7Pb(Mg_(1/3)Nb_(2/3))O_3-0.3PbTiO_3 thin films with different poling directions. For pos-itive poling, pyroelectric current increased with the poling electric field. In the case of negative poling, pyroelectric current decreased with the poling electric field. These results suggest that the good pyroelectric properties of the 0.7Pb (Mg_(1/3)Nb_(2/3))O_3-0.3PbTiO_3 thin films could be due to the presence of self-polarization in this material.