Improvement in dielectric properties of ZrO₂ thin film by employing a Zr precursor with enhanced thermal stability in high-temperature atomic layer deposition

This study explores the challenges associated with the shrinking design rules of dynamic random access memory (DRAM) technology, particularly focusing on the degradation of crystallinity in ZrO₂ insulators within metal-insulator-metal (MIM) capacitors. To mitigate these challenges, a novel high-temperature atomic layer deposition (ALD) process for ZrO₂ is developed, utilizing a newly engineered Zr precursor to enhance thermal stability. Through comprehensive analyses, including thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and thin film growth behavior investigations, the efficacy of the high-temperature ALD process in achieving ZrO₂ thin films with superior crystallinity at process temperatures up to 400 °C was demonstrated. Moreover, X-ray photoelectron spectroscopy (XPS) depth-profile analyses reveal insights into the compositional variations in deposited thin films, while electrical property evaluations in metal-insulator-metal (MIM) capacitor structures highlight the significance of crystallinity enhancement for achieving high dielectric constant of 48.1.