Metal Beta-Diketiminate ALD Precursors for High Purity Dielectric Films
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The integration of alkaline earth metals into vapor deposition processes is challenging due to low volatility and poor reactivity of metal diketonates, which requires high substrate temperatures and strong oxidizers, often resulting in contaminated films.
Innovation Solution
The use of metal-containing compounds with β-diketiminate ligands in atomic layer deposition (ALD) processes, where these compounds are alternately introduced during deposition cycles to form high dielectric metal oxide layers, avoiding the need for high temperatures and oxidizers, and ensuring film purity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If metal diketonates are used in vapor deposition processes, then alkaline earth metal can be deposited, but the low volatility requires dissolution in organic solvent and the poor reactivity requires high substrate temperatures and strong oxidizers, resulting in carbon-contaminated films
Solution Approach 1:
The patent changes the chemical parameters of the metal source by using metal β-diketiminate compounds instead of traditional metal diketonates. This parameter change improves volatility and reactivity, allowing deposition at lower temperatures without strong oxidizers, thereby reducing carbon contamination and simplifying the deposition process
Solution Approach 2:
The patent employs metal β-diketiminate compounds that decompose cleanly during deposition, leaving minimal residue. These compounds act as disposable precursors that sacrifice themselves to form the desired metal oxide film without requiring complex purification steps or strong oxidizing conditions
2Productivity
If high substrate temperatures and strong oxidizers are used to grow films from metal diketonates, then film growth can be achieved, but the films are contaminated with carbon
Solution Approach 1:
The patent changes the thermal and chemical parameters of the deposition process by using metal β-diketiminate compounds that enable film growth at lower temperatures without strong oxidizers. This parameter change eliminates carbon contamination while maintaining productive film growth rates
Solution Approach 2:
The patent converts the potential harm of using organic ligands (carbon contamination) into a benefit by selecting β-diketiminate ligands that decompose cleanly. The organic ligand framework is designed to leave minimal residue, transforming what could be a contamination source into a controlled decomposition process that aids film formation
3Ease of manufacture
If metal compounds with cyclopentadienyl ligands are used, then deposition can proceed, but poor volatility and low thermal stability lead to undesirable pyrolysis on the substrate surface
Solution Approach 1:
The patent changes the ligand type from cyclopentadienyl to β-diketiminate, which fundamentally alters the thermal stability and volatility parameters. The β-diketiminate ligands provide better thermal stability and controlled volatility, preventing pyrolysis on the substrate surface while maintaining deposition feasibility
Solution Approach 2:
The patent uses composite metal β-diketiminate compounds that combine the metal center with specifically designed organic ligands. This composite structure optimizes both volatility for vapor transport and thermal stability to prevent decomposition, achieving a balance that neither pure metal salts nor traditional organometallics can provide
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method enables the formation of high dielectric metal oxide layers with improved purity and reduced contamination, enhancing the deposition process for semiconductor structures and memory devices.
Implementation Method 1
providing a vapor including at least one compound of the formula (Formula I)... contacting the vapor with the substrate to form a metal-containing layer
Implementation Method 2
The metal-containing compounds that include β-diketiminate ligands can advantageously be used in atomic layer deposition methods to deposit, for example, high dielectric films
Implementation Method 3
Metal-containing compounds that include β-diketiminate ligands... M is selected from the group consisting of a Group 2 metal... each L is independently an anionic ligand
Data Source
Figure 1
Figure 2
AI summary
The present invention provides atomic layer deposition systems and methods that include metal compounds with at least one β-diketiminate ligand. Such systems and methods can be useful for depositing metal-containing layers on substrates.