Apparatus and method for improving film thickness uniformity

An apparatus for improving film thickness uniformity, comprising:

• a PECVD machine with twin chambers, each chamber of the twin chambers comprises a wafer heating platform and a radio frequency generator respectively, and at least one of the wafer heating platforms of the chambers is a speed controlled rotating platform;
• wherein, the speed controlled rotating platform is rotated for integral rounds during deposition time, in order to ensure same influence of a radio frequency overlap produced by the two radio frequency generators to inner rings and outer rings of wafers adsorbed on the wafer heating platforms, so as to eliminate abrupt change of film thickness of the wafers caused by the radio frequency overlap;
• wherein, the twin chambers comprise a chamber A and a chamber B which are arranged side by side and connected, the chamber A comprises a wafer heating platform A and a radio frequency generator A, the chamber B comprises a wafer heating platform B and a radio frequency generator B, junction of the chamber A and the chamber B is an opening channel, and the opening channel is located above the wafer heating platform A and the wafer heating platform B;
• a wafer A and a wafer B are transferred to the chamber A and the chamber B respectively, and adsorbed on the wafer heating platform A and the wafer heating platform B for deposition processes.