使用氧化鈦鋯與氧化鈦鑭高介電常數堆疊介電層於金屬-絕緣層-金屬電容之研究

Investigation of High-Performance Metal-Insulator-Metal Capacitor Using ZrTiOx/ZrLaOx Stacked Dielectrics

林郁博(YU-BO LIN)

指導教授 ： 巫勇賢

國立清華大學/原子科學院/工程與系統科學系/碩士(2012年)

https://doi.org/10.6843/NTHU.2012.00656

摘要

在本篇論文中我們探討以ZrLaOx/ZrTiOx/ZrLaOx堆疊介電層作為金屬-絕緣層-金屬(Metal-Insulator-Metal, MIM)電容的介電層。我們發現以單層的ZrTiOx介電層的MIM電容具有負的非線性電壓電容係數，其介電常數高達22.5。而單層的ZrTiOx介電層MIM電容具有正的非線性電壓電容係數和高介電常數25.8。藉由整合ZrLaOx與ZrTiOx兩種金屬氧化物作為MIM電容的介電層，我們實現非線性電壓電容係數的"抵消效應"並且得到高電容密度的成果。以ZrLaOx/ZrTiOx/ZrLaOx堆疊結構的MIM電容可以得到高電容密度14.6 fF/μm2和很小的非線性電壓電容係數33 ppm/V2，並且在頻散現象、溫度穩定性、可靠度方面和不錯的漏電流密度(在-1V時2.5×10-7 A/cm2 )，根據以上結果顯示，ZrLaOx/ZrTiOx/ZrLaOx堆疊介電層應用於下一是世代的高性能MIM電容是具有很大的潛力。

關鍵字

ZrLaO ； ZrTiO ； MIM ； high-k

並列摘要

Metal-insulator-metal (MIM) capacitors with ZrLaOx/ZrTiOx/ZrLaOx laminate as the insulator were explored in this work. Single ZrTiOx dielectric was found to have a negative quadratic voltage coefficient of capacitance (VCC-α) with a high-κ value of 22.5. By integrating this dielectric with ZrLaOx which provides a positive VCC-α and a high κ value of 25.8, the “canceling effect” of VCC-α can be achieved while a high capacitance density can be maintained. MIM capacitors with the laminate structure display desirable characteristics in terms of a capacitance density of 14.6 fF/μm2, a low VCC-α of 33 ppm/V2, negligible frequency dispersion and satisfactory leakage current of 2.5×10-7 A/cm2 at -1 V. These results show that the ZrLaOx/ZrTiOx/ZrLaOx laminate holds the great potential to be applied to next-generation high-performance MIM capacitors.

參考文獻

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