Dicyanide-Based N-Type Semiconductors for Air-Stable Organic Electronics

The patent applies parameter changes by systematically modifying the LUMO energy level of n-type organic semiconductors through chemical structure design. Specifically, it develops materials with LUMO energy levels below −4.1 eV (e.g., −4.5 eV to −5.0 eV), which is a critical parameter threshold that transforms the material's interaction with moisture and oxygen, thereby achieving air stability without requiring complex encapsulation or inert atmospheres.

The patent employs composite materials by combining electron-deficient building blocks (such as benzodifurandione, naphthalene diimide, and triphenylene diimide) with specific side chain structures. This composite approach creates materials that simultaneously achieve low LUMO energy levels for air stability and high solubility for solution processing, resolving the contradiction between stability and processability.

The patent applies local quality by introducing specific side chain structures (such as alkoxy, alkyl, or aryl groups) at localized positions on the electron-deficient core. These side chains are strategically placed to provide solubility enhancement without significantly affecting the core's electron-accepting capability and low LUMO energy level, thus maintaining air stability while enabling solution processing.

The patent modifies the solubility parameter by changing the chemical structure of side chains attached to the electron-deficient core. By adjusting side chain length, branching, and functional groups, the material achieves optimal solubility in common organic solvents (e.g., chloroform, toluene, THF) while preserving the low LUMO energy level required for air stability.

The patent replaces expensive and complex fluorine substitution with alternative electron-deficient building blocks that inherently provide low LUMO energy levels. These alternative structures (such as benzodifurandione, naphthalene diimide, and triphenylene diimide derivatives) can be synthesized through more straightforward and cost-effective routes, reducing both synthetic complexity and production cost while maintaining air stability.

The patent uses composite materials by combining different electron-deficient building blocks with suitable side chains to achieve the desired low LUMO energy level without relying on multiple fluorine substitutions. This composite strategy simplifies the synthesis pathway and reduces costs compared to multi-step fluorination processes.

The patent changes the critical parameter of LUMO energy level to below −4.1 eV, which fundamentally alters the material's chemical stability in air. This parameter change ensures that the material does not undergo degradation reactions with moisture and oxygen, thereby maintaining high electron transport performance (e.g., electron mobility > 10⁻⁴ cm²/Vs) over extended periods without performance decay.

The patent achieves excessive air stability by designing materials with LUMO energy levels significantly lower than the threshold (e.g., −4.5 eV to −5.0 eV instead of just below −4.1 eV). This excessive lowering of LUMO energy level provides a larger energy margin that further enhances resistance to environmental degradation, ensuring long-term durability for CMOS integrated circuits.