红外与激光工程
紅外與激光工程
홍외여격광공정
INFRARED AND LASER ENGINEERING
2013年
8期
2181-2185
,共5页
张连东%冯刘%刘晖%程宏昌%高翔%苗壮
張連東%馮劉%劉暉%程宏昌%高翔%苗壯
장련동%풍류%류휘%정굉창%고상%묘장
GaAs光阴极%三偶极子模型%表面势垒%电势分布
GaAs光陰極%三偶極子模型%錶麵勢壘%電勢分佈
GaAs광음겁%삼우겁자모형%표면세루%전세분포
GaAs photocathode%three dipole model%surface barrier%potential distribution
根据激活过程中光电流变化规律及原位光谱响应测试,模拟了GaAs光阴极表面势垒的形成过程,在光阴极表面双偶极子模型的基础上作了修正,建立了三偶极子模型。新模型认为,光阴极表面势垒由三个偶极层套构而成,第一偶极层由GaAs(Zn)--Cs+偶极子组成,第二偶极层由Cs2O偶极子组成,第三偶极层由GaAs-O-Cs偶极子组成,第二、三偶极层嵌入第一偶极层中。根据隧道效应与量子效率测试结果,确立了势垒中分段均匀的电势分布,计算得出势垒宽度为1.65 nm,有效电子亲和势为-0.44 eV。新模型的建立对理解光电阴极表面发射机理具有重要意义。
根據激活過程中光電流變化規律及原位光譜響應測試,模擬瞭GaAs光陰極錶麵勢壘的形成過程,在光陰極錶麵雙偶極子模型的基礎上作瞭脩正,建立瞭三偶極子模型。新模型認為,光陰極錶麵勢壘由三箇偶極層套構而成,第一偶極層由GaAs(Zn)--Cs+偶極子組成,第二偶極層由Cs2O偶極子組成,第三偶極層由GaAs-O-Cs偶極子組成,第二、三偶極層嵌入第一偶極層中。根據隧道效應與量子效率測試結果,確立瞭勢壘中分段均勻的電勢分佈,計算得齣勢壘寬度為1.65 nm,有效電子親和勢為-0.44 eV。新模型的建立對理解光電陰極錶麵髮射機理具有重要意義。
근거격활과정중광전류변화규률급원위광보향응측시,모의료GaAs광음겁표면세루적형성과정,재광음겁표면쌍우겁자모형적기출상작료수정,건립료삼우겁자모형。신모형인위,광음겁표면세루유삼개우겁층투구이성,제일우겁층유GaAs(Zn)--Cs+우겁자조성,제이우겁층유Cs2O우겁자조성,제삼우겁층유GaAs-O-Cs우겁자조성,제이、삼우겁층감입제일우겁층중。근거수도효응여양자효솔측시결과,학립료세루중분단균균적전세분포,계산득출세루관도위1.65 nm,유효전자친화세위-0.44 eV。신모형적건립대리해광전음겁표면발사궤리구유중요의의。
The photocathode surface barrier formation process of the GaAs photocathode was simulated according to the variation of the photocurrent while the photocathode was activating and in situ tests of spectra response, the two-dipole model was amended to establish a three dipole model. It was considered from the new model that the photocathode surface barrier formed by three kind of dipole layers, the first dipole layer was composed of GaAs(Zn)--Cs+dipole, the second dipole layer was composed of Cs2O dipole and the third dipole layer was composed of GaAs-O-Cs dipole, the second and third dipole layer embedded in the first dipole layer. The barrier potential distribution which was piecewise uniform was established according to tunnel effect and results of quantum efficiency tests, it was calculated that the width of the barrier is 1.65 nm, and the effective electron affinity energy is -0.44 eV. The establishment of the new model is of great significance to further understand the photocathode surface emission mechanism.