In the field of semiconductor manufacturing, the advancement and optimization of materials used for decoupling capacitors are crucial for enhancing device performance and reliability. This study provides a detailed comparative analysis of two generations of metalorganic hafnium precursors used in atomic layer deposition (ALD) of high-k dielectrics, specifically focusing on their application in Metal-Insulator-Metal (MIM) decoupling capacitors. The precursors in question are the first-generation Tetrakis(ethylmethylamido)hafnium (TEMAHf) and the third-generation AirLiquide Kahe. Initially, the study, based on previous research with Kahe [1], involved a comprehensive assessment of the new third-generation precursor Kahe, to evaluate its behavior under various ALD conditions. Parameters such as bubbler temperature (TB), purge time (tP), precursor pulse time (tKahe), ozone exposure time (tO3), chamber pressure, and deposition temperature (TD) were experimented. The optimal bubbler temperature was found to be 110°C. It was determined that the best purge option was a pulse time of 20s, as extending the purge time beyond 30s significantly decreased the deposition rate. The optimal Kahe pulse time was found to be 4s. Interestingly, a longer ozone exposure time of 4s was the best option as it reduced the deposition rate while improving thickness non-uniformity. Lowering the chamber pressure improved uniformity but at the cost of a reduced deposition rate. The deposition temperature was evaluated up to 450°C (upper BEoL thermal budget), with an optimal balance between non-uniformity and carbon impurities achieved at 350°C. In all instances, the growth per cycle demonstrated a linear trend, confirming that Kahe deposition at such elevated temperatures has not yet reached the saturation point of the ALD window. Following the characterization of the ALD process, MIM capacitors were fabricated using HfO2/Al2O3/HfO2 (HAH) dielectrics. Al2O3 was specifically chosen to maintain the devices in an amorphous state during deposition, thereby reducing leakage current while achieving better field linearity and reliability. The deposition temperatures were set at 313°C for TEMAHf and 350°C and 400°C for Kahe, with Tri-methyl-aluminum used as the aluminum precursor. Compared to TEMAHf, Kahe provides a more uniform deposition across the 300mm wafers; notably, the deviation decreases as the deposition temperature increases. Both TEMAHf-based and Kahe-based HAH samples remain amorphous during deposition. The comparative analysis covered several key electrical characteristics of MIM capacitors, such as capacitance density, field linearity (α), leakage current behavior, and dielectric breakdown. These properties are essential for determining the suitability of the dielectrics for decoupling applications, where stable capacitance and low leakage currents are paramount. In terms of capacitance density, Kahe provides a more stable performance across applied frequencies, showing less dispersion and maintaining levels up for almost four orders of frequency. Field linearity is smoother with Kahe over frequency, displaying 200 ppm/(MV/cm)² lower values than TEMAHf at low frequencies. Remarkably low leakage currents were observed at operating field conditions of up to 1.5 MV/cm. Leakage-current density curves between TEMAHf-based and Kahe-based MIM at TD=350°C are quite similar across all applied temperatures (TM=25-125°C), including similar breakdown points, with a slight improvement for Kahe at TD=350°C. However, Kahe at TD=400°C shows a dielectric breakdown nearly 2MV/cm lower, likely due to higher carbon impurities increasing defects and causing earlier breakdowns. Moreover, the electrical reliability of the capacitors was investigated in terms of time-dependent-dielectric-breakdown (TDDB) to ensure long-term performance stability under various external conditions, which is particularly important for applications in environments where capacitors are subjected to fluctuating temperatures and voltages. Kahe-based HAH at TD=350°C has a better slope and therefore extrapolation behavior even with the most conservative extrapolation models applied, at the highest applicable temperature of 125°C. Thus, Kahe samples meet the industrial standard of a 10-year lifetime under operating conditions at 125°C, fulfilling automotive standards that require such performance [2]. This significant advantage highlights Kahe's superiority in meeting demanding industrial standards for reliability purposes. In conclusion, this comparative analysis not only emphasizes the advancements in precursor chemistry for ALD of high-k dielectrics but also highlights the critical role of optimized deposition parameters in achieving desired electrical properties for decoupling capacitors. The insights gained from this study are expected to guide future developments in capacitor technology, contributing to the enhancement of overall device performance and reliability in semiconductor applications. References: [1] Viegas et al., Incipient Ferroelectric Properties in as-deposited Hafnium Zirconium Oxide for BEOL Applications, AVS 24th International Conference on ALD, 2024, Helsinki, Finland [2] AEC-Q100, Rev. J, 2023, USA Figure 1