NINGBO INNO PHARMCHEM CO.,LTD. is dedicated to advancing the performance of organic electronics, with a particular focus on developing highly sensitive gas sensors based on organic field-effect transistors (OFETs). A crucial element in this development is the precise control over the crystallization of organic semiconductor materials, such as TIPS-pentacene, within the active sensing layer.

Our research has demonstrated that the morphology and crystalline structure of TIPS-pentacene films are significantly influenced by the spin-coating process, particularly the spin-coating time. When TIPS-pentacene is blended with insulating polymers, like polystyrene (PS), and deposited using spin-coating, the amount of residual solvent plays a key role in determining the growth mode of the TIPS-pentacene crystals. Shorter spin times often lead to a higher residual solvent content, promoting one-dimensional (1D) crystal growth. In contrast, optimized longer spin times result in a controlled residual solvent environment that favors two-dimensional (2D) crystal growth, often in the form of spherulites.

This shift in crystallization mode has profound implications for gas sensing. The 2D crystalline films, characterized by a more continuous and often porous structure, offer a larger surface area and better accessibility for analyte molecules to interact with the semiconductor material. This is critical for achieving high sensitivity and rapid response times in gas sensors. The porous nature allows gases to penetrate the active layer more easily, leading to a more significant change in the electrical signal when exposed to target analytes like NO2. Therefore, achieving 2D crystal growth of TIPS-pentacene is a key strategy for enhancing sensor performance.

Understanding the effect of spin coating time on TIPS-pentacene morphology is therefore essential for optimizing the fabrication of these devices. By fine-tuning the spin-coating parameters, we can reliably produce films with the desired crystalline structures. This control directly impacts the TIPS-pentacene PS blend gas sensing properties. The ability to reliably fabricate films that exhibit improved TIPS-pentacene PS blend OFET characteristics, specifically for sensing applications, is a major focus for NINGBO INNO PHARMCHEM CO.,LTD.

Our ongoing commitment to material science and process optimization ensures that we are continually enhancing the capabilities of organic gas sensors, making them more accurate, responsive, and practical for a wide range of applications.