Tien Chuen-Lin, Chen Kuan-Po, Lin Hong-Yi
Department of Electrical Engineering, Feng Chia University, Taichung 40724, Taiwan.
Ph. D. Program of Electrical and Communications Engineering, Feng Chia University, Taichung 40724, Taiwan.
Materials (Basel). 2021 Feb 26;14(5):1101. doi: 10.3390/ma14051101.
We present an experimental method for evaluating interfacial force per width and predicting internal stress in mid-infrared band-pass filters (MIR-BPF). The interfacial force per width between the two kinds of thin-film materials was obtained by experimental measurement values, and the residual stress of the multilayer thin films was predicted by the modified Ennos formula. A dual electron beam evaporation system combined with ion-assisted deposition was used to fabricate mid-infrared band-pass filters. The interfacial forces per width for Ge/SiO and SiO/Ge were 124.9 N/m and 127.6 N/m, respectively. The difference between the measured stress and predicted stress in the 23-layer MIR-BPF was below 0.059 GPa. The residual stresses of the four-layer film, as well as the 20-layer and 23-layer mid-infrared band-pass filter, were predicted by adding the interface stress to the modified Ennos formula. In the four-layer film, the difference between the predicted value and the measured stress of the HL (high-low refractive index) and LH (low-high refractive index) stacks were -0.384 GPa for (HL) and -0.436 GPa for (LH), respectively. The predicted stress and the measured stress of the 20-layer mid-infrared filter were -0.316 GPa and -0.250 GPa. The predicted stress and the measured stress of the 23-layer mid-infrared filter were -0.257 GPa and -0.198 GPa, respectively.
我们提出了一种用于评估中红外带通滤波器（MIR-BPF）中单位宽度界面力和预测内部应力的实验方法。通过实验测量值获得了两种薄膜材料之间的单位宽度界面力，并利用修正的恩诺斯公式预测了多层薄膜的残余应力。采用双电子束蒸发系统结合离子辅助沉积来制备中红外带通滤波器。Ge/SiO和SiO/Ge的单位宽度界面力分别为124.9 N/m和127.6 N/m。23层MIR-BPF中测量应力与预测应力之间的差异低于0.059 GPa。通过将界面应力添加到修正的恩诺斯公式中，预测了四层薄膜以及20层和23层中红外带通滤波器的残余应力。在四层薄膜中，HL（高低折射率）和LH（低高折射率）堆叠的预测值与测量应力之间的差异，对于（HL）为-0.384 GPa，对于（LH）为-0.436 GPa。20层中红外滤波器的预测应力和测量应力分别为-0.316 GPa和-0.250 GPa。23层中红外滤波器的预测应力和测量应力分别为-0.257 GPa和-0.198 GPa。
