Metal Borate p-Dopants for OLED Hole Transport Layers

The patent applies parameter changes by systematically varying the metal cation identity (Li⁺, Na⁺, K⁺, Cs⁺, Ca²⁺, Sr²⁺, Ba²⁺), the anionic ligand structure (different borate, phosphate, sulfonate, carboxylate groups), and their stoichiometric ratios to optimize the balance between conductivity and crosstalk suppression. This allows tuning the electrical properties to achieve both low crosstalk and adequate hole transport.

The patent employs composite materials by combining organic hole transport matrices (such as TCTA, TAPC, TPD) with inorganic metal salt or metal complex dopants. This composite approach creates a hybrid system where the organic matrix provides structural integrity and the inorganic dopant provides controlled conductivity, thereby reducing electrical crosstalk while maintaining device stability.

The patent demonstrates universality by showing that metal salts and metal complexes with specific anionic ligands can serve as effective p-dopants across multiple device types and configurations. The same class of dopants can be adapted for different hole transport matrices and device architectures, reducing the need to develop entirely separate material classes for each application.

The patent applies parameter changes by modifying the metal cation identity and anionic ligand structure within a single dopant class to achieve the desired performance for different applications. This approach maintains material versatility while avoiding the complexity of developing multiple structurally different material classes.