Complex sentence: However, the early ATO films production technology was unstable and it was only until 1999, production breakthrough was achieved for Antimony Tin Oxide films and in early 2000s, most of the Japanese Antimony Tin Oxide films were procured by FilmTack's associated companies in Singapore.
Split into simpler sentences: However, the early ATO films production technology was unstable and it was only until 1999, production breakthrough was achieved for Antimony Tin Oxide films. By the early 2000s, most of the Japanese Antimony Tin Oxide films were procured by FilmTack's associated companies in Singapore.