AbstractAn in-situ technique for observing formation process of organic-siloxane contamination at a head-disk interface was developed. The observations show that the development process of the contamination consists of two steps: initiation of a contamination seed and growth of the seed. The initiation time of the contamination seed is much longer than the growth time of the contamination. Furthermore, the contamination is always initiated at the slider's trailing edge (the lowest position of a flying slider). These results suggest that the development process of the contamination is contact/friction activated. Moreover, it was found that the initiation time of the contamination significantly decreases, but the growth time of the contamination slightly decreases, as the slider's flying height decreases. It was also found that the initiation time of the contamination on a textured disk is longer than that on a smooth disk, and the growth time of the contamination is almost unaffected by the disk texture.