Effects of deposition parameters on properties of high resistance CrSi-based thin-film resistors

Cr is a metal with lower resistivity (as compared with Si) and positive temperature coefficient of resistance (TCR value) and Si is a semiconductive material with higher resistivity and negative TCR value. For that, the commercial-grade targets of 28 wt.% Cr-72 wt.% Si, 40 wt.% Cr-60 wt.% Si and 55 wt.% Cr-45 wt.% Si were used to deposit the thin-film materials using sputtering method at the same parameters, and their physical and electrical properties were measured and compared under different deposition powers. The crystallization and the surface morphology of the CrSi-based thin-film resistors were measured using X-ray diffraction (XRD) pattern and field emission scanning electron microscopy (FESEM). In order to find the effect of deposition power on the average atomic ratio of Cr and Si, the elemental ratios were also measured as a function of deposition power for different CrSi-based targets by FESEM equipped with Energy-Dispersive X-ray spectroscopy (EDX) for elemental Cr and Si. The effects of Cr concentration and deposition power on the sheet resistances, resistivity and TCR values of the deposited CrSi-based thin-film resistors were also well measured and compared, and the reasons to cause the variations of resistivity and TCR values were also investigated and discussed.