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The manipulation of temperature coefficient of resistance (TCR) in TaN thin-film resistor (TFR) was demonstrated by electrical measurement and analysis through supercritical carbon dioxide (SCCO2 fluid treatment for the first time. The negative TCR value of TaN TFR changes to positive TCR value through annealing process due to the growth and merge of TaNx grain. After SCCO2 treatment, the positive TCR value was changed back to negative TCR value in TaN TFR. The TaN grain boundary isolated by dehydroxyl effect of SCCO2 fluid treatment causes the current conduction mechanism changed to hopping conduction from ohmic conduction. [ABSTRACT FROM AUTHOR]

TaHf thin films were deposited by performing the cosputtering of Ta and Hf targets. The results indicated that TaHf alloy is suitable for use as a resistive layer for thin film chip resistors and a replacement for NiCr and TaN x alloys. Maintaining the Hf:Ta ratio at approximately 1:1 produced the highest resistivity of 5.7 × 10−4 Ωcm when compared with TaN x and NiCr alloy thin films. This ratio also yielded a smaller temperature coefficient of resistance of −330 ppm/°C compared with TaN x thin films. Furthermore, the temperature coefficient of resistance of most TaHf thin films could be adjusted closer to zero through annealing. The increased Hf content in TaHf alloy was attributed to its poorer thermal stability and anticorrosion property relative to pure Ta films. However, the anticorrosion property of TaHf thin films was still stronger than that of NiCr thin films. • TaHf is a promising alternative material to TaN and NiCr for thin film resistor applications. • TaHf thin film possesses a smaller TCR and higher resistivity compared to TaN. • Anticorrosion properties of TaHf are stronger than those of NiCr. • TaHf thin film achieves a near-zero TCR by annealing if its oxygen content is low. [ABSTRACT FROM AUTHOR]

Ta–N–Al thin films were produced by reactive sputtering with two different TaAl alloys (Al 10 at.% and 20 at.%) for use as resistive materials for thin film chip resistors. Changing the N 2 gas flow of the N 2 /Ar plasma and the Al ratio in TaAl alloy resulted in different microstructures and electrical properties of the Ta–N–Al thin film. The resistivity of the thin film sputtered by TaAl (Al 20 at.%) alloy was 1.23 times that sputtered by Ta under 20% N 2 /Ar. After deposition, rapid thermal processing was applied to anneal the thin films for 5 min at 600 °C, 650 °C, and 700 °C under N 2 (99.995%) atmosphere, causing the Ta 2 N and TaN crystalline phase formation. Al in Ta–N–Al was observed to hinder Ta 2 N and TaN crystalline phase formation during annealing. It is crucial to dope Al ith Ta–N appropriately to obtain a near-zero temperature coefficient of resistance (TCR) after annealing. The TCR of Ta–N–Al thin film, sputtered by TaAl (Al 20 at.%) alloy, was substantially affected by the annealing temperature. However, the thin film sputtered by TaAl (Al 10 at.%) alloy under 16% N 2 /Ar can achieve a TCR of −1.8 ppm/°C and 1.4 ppm/°C after annealing at 600 °C and 650 °C, respectively. • Ta-N-Al with adequate Al has a higher resistivity than Ta-N. • Get near-zero TCR of Ta-N-Al by annealing within a specific temperature range. • Al in Ta-N-Al hinders Ta 2 N and TaN grain growth during annealing. [ABSTRACT FROM AUTHOR]