Novel Complexes for Oxide Deposition (18-Jan-2010)

Disclosed herein are non-limiting embodiments of compositions and methods for manufacturing of semiconductor, photovoltaic, LCD-TFT, or flat panel devices.

Description

One of the serious challenges the industry faces is developing new gate dielectric materials for DRAM and transistors.  For decades, silicon dioxide (SiO₂) was a reliable dielectric, but as transistors have continued to shrink and the technology moved from “Full Si” transistor to “Metal Gate/High-k” transistors, the reliability of the SiO₂-based gate dielectric is reaching its physical limits.  The need for new high dielectric constant material and processes is increasing and it becomes more and more critical as the size for current technology is shrinking.  Dielectric materials containing alkaline earth metals such as SrTiO₃ can provide a significant advantage in capacitance compared to conventional dielectric materials.

However, alkaline earth metal deposition is difficult and chemical and physical properties become more and more important.  For instance, atomic layer deposition, ALD, has been identified as an important thin film growth technique for microelectronics manufacturing, relying on sequential and saturating surface reactions of alternatively applied precursors, separated by inert gas purging.  The surface-controlled nature of ALD enables the growth of thin films of high conformality and uniformity with an accurate thickness control.  Unfortunately the successful integration of alkaline earth metals into vapor deposition processes has proven to be difficult.

Although atomic layer deposition (ALD) of alkaline earth metal diketonates has been disclosed, these metal diketonates have low volatility, which typically requires the use of organic solvent for use in a liquid injection system, high addition to low volatility, these metal diketonates generally have poor reactivity, often requiring high substrate temperatures and strong oxidizers to grow a film, which is often contaminated with carbon.  Other alkaline earth metal sources, such as those including substituted or unsubstituted cyclopentadienyl ligands, typically have poor volatility as well as low thermal stability, leading to undesirable pyrolysis on the substrate surface.

Other sources and methods of incorporating high dielectric materials are being sought for new generations of integrated circuit devices.

Summary of the Invention

Embodiments of the present invention provide the methods of using metal-containing compounds (i.e., metal-containing complexes, precursors) that include at least one complex described by formula I:

Formula I:

where M is an alkaline earth, preferably strontium or barium

X is selected from: O, S, NR⁷

Each R is a hydrogen or carbyl group independently selected to the others.

R² and R⁵ are preferably H

R^1...