Two-dimensional model of a large area, inductively coupled, rectangular plasma source for chemical vapor deposition

A novel design for an inductively coupled, rectangular plasma source is des cribed. The design encompasses several key issues of large area thin film g rowth by chemical vapor deposition: structural integrity, electrostatic scr eening, substrate temperature control, and maximal growth surface. A test r eactor has been utilized to grow diamond films over similar to 1800 cm(2) a t 13 MHz and similar to 1 torr pressure with 45 kW coupled power. The desig n is readily scalable to larger areas. To analyze the axial plasma uniformi ty, a two-dimensional (2-D) simulation model is presented. The electromagne tic coupling, nonequilibrium plasma chemistry, and multispecies diffusion a re self-consistently treated. In this 2-D approach, the slotted Faraday scr een behaves as a diamagnetic medium in transmitting the magnetic field. Res ults are compared with experimental data for the hydrogen plasma extent, el ectron, and gas temperatures. Neutral gas thermal conduction and hydrogen r ecombination dominate the energy deposition to the wall, and in turn govern the plasma length. A tradeoff between quality and growth area is predicted for the reactor as the pressure is decreased.