In this report, we describe the two different nickel oxide film formation processes for microbolometer application:
the heat treatment of nickel metal and the reactive sputtering. Nickel oxide films obtained by the heat treatment of nickel
show high TCR(about -3.2/°C) and low 1/f noise characteristic. The reactively sputtered nickel oxide films have the wide
range of resistivity according to the sputtering vacuum level, time, and O2/Ar gas partial pressure. The acquired TCR of
sputtered films are in the range of -1.4%/°C and -3.45%°C. And the 1/f noise parameter k, which shows the performance
between VOx and a-Si, is as low as 8.5×10-13 at the TCR of -1.75%/°C. Acquired nickel oxide films were analyzed from
XRD, AFM methods, and etc. It is regarded that the resistivity variation of polycrystalline nickel oxide film comes from
nonstoichiometric property of nickel and oxygen atoms. We simulated the optic and membrane structure for predicting
the performance of a microbolometer with nickel oxide film. The estimated NETD(noise equivalent temperature
difference) for the 50μmx50μm size of pixel is NETD below 20mK.
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