采用p-InP/n-InGaAs/n-InP外延异质结材料,制备了InGaAs线列台面探测器,并测试了器件的I-V曲线、响应率和噪声。通过拟合I-V曲线得到了器件的理想因子和串联电阻,并分析了它们对器件响应率和噪声的影响。结果表明:InGaAs吸收层外延质量与器件的理想因子相关联,影响器件的噪声,但对器件的响应率影响不大。计算了无光照和有光照情况下串联电阻Rs取不同值时器件的I-V曲线,得到串联电阻较小时其作用可忽略,但串联电阻会表观上增大零偏电阻,且串联电阻越大,损失的光电流越多。实验结果证明该方法对改进器件性能有一定的参考意义。
The InGaAs linear mesa detector was fabricated with p-InP/n-InGaAs/n-InP heterojunction material,and its current-voltage (I-V) curve,responsivity and noise were systematically investigated. The ideality factor and series resistance were obtained by fitting the I-V curve,and their effect on responsivity and noise of the detector was analyzed. The results indicate that the ideality factor is in correlation with the quality of InGaAs epitaxial layer,which affects the noise greatly,but it is not the case of the responsivity.And the series resistance had little impact on the noise and responsivity of the detectors. The I-V characteristics of the detector were estimated theoretically with the different series resistance under the illuminated and un-illuminated condition. The theoretical results indicates that the series resistance has little effect on the performance of the detector when its value is small,but it would increase the observed zero-bias resistance and decreases the output of photocurrent. When the series resistant is 1000Ω,the signal current starts to be lost under the condition of photocurrent is 4×10^-4 A, but when the series resistant is 10000Ω,the signal current starts to be lost under the condition of photocurrent is 3×10^-5 A.The proposed method is helpful to improve the characteristics of InGaAs detector.