Patent ID: 9059678
Filing Date: 2015-06-16
Classification: H03H

Abstract:
1. A match circuit coupled between an RF source and a plasma chamber, the match circuit comprising: a power input circuit, the power input circuit coupled to an RF source; an inner coil input circuit coupled between the power input circuit and an input terminal of an inner coil, the inner coil input circuit including an inductor and a first variable capacitor coupled in series to the inductor, the inductor connecting to the power input circuit, and the capacitor connecting to the input terminal of the inner coil, a first node being defined between the power input circuit and the inner coil input circuit, wherein the inductor has a value of 0.3 uH to 0.5 uH; an inner coil output circuit coupled between an output terminal of the inner coil and ground, the inner coil output circuit defining a direct pass-through connection that does not include an inductor or capacitor and is a direct connection to ground; an outer coil input circuit coupled between the first node and an input terminal of an outer coil, the outer coil input circuit having a second variable capacitor, the outer coil input circuit further coupled to the power input circuit via the first node; an outer coil output circuit coupled between an output terminal of the outer coil and ground, wherein the outer coil output circuit includes a third capacitor having a value of about 80 pF to about 120 pF; wherein the first node splits power from the power input circuit for distribution to the inner coil input circuit and the outer coil input circuit, the first and second variable capacitors providing for tuning of a ratio of currents between the inner coil and the outer coil.