Surface treatment producing high conductivity vias with simultaneous polymer adhesion
Treatment solutions and methods for treating a substrate including forming a first layer on a surface of the substrate, providing a process gas to the one or more plasma sources, the process gas includes a gas mixture of a reactive gas species and an inert gas species; forming a plasma under vacuum in the one or more plasma sources; and exposing the substrate to the plasma under vacuum to treat the first layer on the surface of the substrate.
1 . A method of treating a substrate comprising:
forming a first layer on a surface of the substrate;
providing a process gas to one or more plasma sources, the process gas includes a gas mixture of a reactive gas species and optionally inert gas species and wherein the one or more plasma sources generate plasma by implementing an operation of linear ion sources by AC excitation;
forming a plasma of the reactive species under vacuum in the one or more plasma sources;
moving the substrate by carrying the substrate on a substrate web at a speed between 1 meter/minute to 3 meter/minute, and wherein the substrate is biased by 13.56 MHz capacitive discharge for processing a 300 mm by 400 mm substrate; and
exposing the substrate to the plasma of the reactive species under vacuum to chemically remove contaminants from the first layer on the surface of the substrate by chemical reduction while maintaining the first layer intact;
wherein the one or more plasma sources include one or more plasma generators that operate in a vacuum environment at a pressure of about 0.5 to 2 milliTorr.
2 . The method of claim 1 , applying a voltage discharge that split ammonia into hydrogen and nitrogen species, wherein the voltage discharge is between 1,500 V and about 5,000 V and the voltage discharge has a frequency between about 20 kHz to 50 kHz and about 100 kHz to 500 kHz.
3 . The method of claim 2 , wherein the voltage discharge is between 2,500 V and 3,000 V.
4 . The method of claim 1 , wherein the reactive gas species include ammonia.
5 . The method of claim 1 , wherein the inert gas species includes at least one of nitrogen, helium, argon, neon, krypton and xenon.
6 . The method of claim 1 , wherein the step of providing the process gas further comprises flowing the process gas into a discharge section of the one or more plasma sources.
7 . The method of claim 1 , wherein the plasma can include radicals and ions of the process gas.
8 . The method of claim 1 , wherein the step of forming the plasma further comprises applying a voltage discharge at a pulse generator to the one or more plasma sources, wherein the applied voltage enables accelerating voltages that split ammonia into hydrogen and nitrogen species.
9 . The method of claim 1 , wherein the step of forming the plasma further comprises producing electric currents by electromagnetic induction by time-varying magnetic fields to form inductively coupled plasma.
10 . The method of claim 9 , wherein the step of forming the plasma further comprises passing a time-varying electric current through a coil to create a time-varying magnetic field around the coil, which in turn induces azimuthal electric field in a rarefied gas, wherein the rarefied gas is argon.
11 . The method of claim 1 , wherein the first layer includes any exposed surface of the substrate which may be comprised of copper or alloys thereof, steel, stainless steel, electroless nickel, or nickel, and treatment of the first layer includes removal of oxides, carbon compounds, or other contaminants from the exposed surfaces of the substrate.
12 . The method of claim 1 , further comprising depositing a second layer over the first layer after exposing the first layer to the plasma.