Silecs has introduced the SC series of products for use as advanced optical coatings in state-of-the-art CMOS image sensor (CIS) production. Digital image sensors manufactured with low-cost CMOS semiconductor processes have recently become a key component in many applications. Using its unique molecular engineering approach, Silecs has developed its SC product line series to improve the reliability and optical efficiency of CMOS image sensors, enabling enhanced image quality for end users.
According to Fred McNeil, vice president of sales, a lot of the coatings in use today are organic polymers. Whereas Silec’s products are silicon based and are able to transmit almost 100% at the visible range, as one would expect of a glass-like structure. In addition, the coatings can be annealed at a lower temperature and their characteristics do not degrade over time, as is often the case when organic coatings are subjected to ultraviolet light.
“Though the old materials were fine when pixel sizes were larger, they don’t satisfy the needs as pixel densities increase, which is why materials with better optical properties and better thermal properties have become so essential,” said McNeil.
By transforming CMOS device lines to CMOS sensor manufacture is bringing new life to old CMOS process lines, thereby opening new market opportunities for process lines. This is really no surprise given that the demand for CMOS image sensors is growing so rapidly in military and commercial markets.
The SC 100 and SC 200 products are used primarily to coat and protect microlens arrays on the CIS chip surface. SC 300 is designed for planarization and passivation between the color filter and microlens arrays, and provides UV blocking for further device protection. SC 400 is designed to planarize high-aspect-ratio, deep-trench applications up to five microns in depth, while maintaining high crack resistance and thermal stability up to 450 degrees C. In addition to outstanding optical properties, all the SC products exhibit excellent electrical performance and are compatible with etchback and CMP processes.