钝化膜应力对锑化铟器件性能的影响

Effect of Passivation Film Stress on the Performance of InSb Devices

随着InSb红外探测器关键尺寸的不断缩小,钝化膜应力的大小对器件I-V性能的影响越发明显。为了降低探测器芯片的应力,研究了一种由SiO2和SiON组成的复合钝化膜体系。通过改变气体的射频时间,在InSb晶片上淀积厚度分别为300 nm、500 nm、700 nm和900 nm的钝化膜,测量并计算了不同厚度钝化膜的应力。当厚度为700 nm时,钝化膜的应力最小值为-1.78 MPa。研究了具有不同应力钝化膜的器件的I-V特性,发现厚度为700 nm时InSb芯片具有更加优异的I-V特性。通过调整复合钝化膜的厚度,降低了钝化膜的应力,有效地提升了InSb探测器的性能。

With the decreasing of the key size of InSb infrared detector,the influence of the passivation film stress on the I-V performance of the device becomes more and more obvious.In order to reduce the stress of the detector chip,a composite passivation film system consisting of SiO2and SiON was studied.Passivation films with thicknesses of 300 nm,500 nm,700 nm and 900 nm were deposited on InSb wafers by varying the radio frequency(RF)time of the gas.The stresses of passivation films with different thicknesses were measured and calculated.When the thickness is 700 nm,the minimum stress of the passivation film is-1.78 MPa.The I-V characteristics of devices with different stress passivation films are investigated.It is found that the InSb chip has better I-V characteristics when the thickness is 700 nm.By adjusting the thickness of composite passivation film,the stress of passivation film is reduced,and the performance of InSb detector is effectively improved.