Method and apparatus for plating solution analysis and control

摘要

A plating system comprises a plating solution and an apparatus for control of the plating solution, the apparatus including a Raman spectrometer for measurement of organic components, a visible light spectrometer for measurement of metallic components, and a pH probe. The plating solution can be sampled continuously or at intervals. Dosing of the plating solution adjusts for components consumed or lost in the plating process. The method of dosing is based on maintaining a desired composition of the plating solution.

主权项

1. A system used in electroless plating of metallic compounds, the system comprising:
a visible light spectrometer configured for visible light measurement technique to measure an absorbance of the plating solution, the absorbance of the plating solution being an indication of the concentration of different metal ions in the plating solution; a Raman spectrometer configured for Raman measurement technique to measure a concentration of a reducing agent in the plating solution; a pH probe configured to measure a pH level of the plating solution; a sampling system comprising a flow cell, configured to measure components of a plating solution, the plating solution having a reducing agent, a pH adjusting agent, and at least one metal in solution, the sampling system further configured to divert a portion of the plating solution to the Raman spectrometer to measure a concentration of the reducing agent, the sampling system also to divert a portion of the plating solution to the visible light spectrometer (VIS) to measure a concentration of different metal ions in solution, the sampling system further to divert a portion of the plating solution to the pH probe to measure a pH level of the plating solution, wherein the Raman spectrometer and the visible light spectrometer are operatively connected to the flow cell in parallel and the flow cell is fluidly connected to the pH probe; and a control system connected to the visible light spectrometer, the Raman spectrometer, and the pH probe, the control system being configured to utilize the measurements of the visible light spectrometer, the Raman spectrometer, and the pH probe to determine dosing additions of a chemical makeup solution, the reducing agent, a pH adjusting solution, and deionized (DI) water to the plating solution, the dosing additions functioning to replace plating solution components diminished by a plating process, and to determine replenishment additions of the chemical makeup solution, the reducing agent, the pH adjusting solution, and deionized (DI) water to the plating solution, the replenishment additions functioning to maintain a target volume of the plating solution and to replenish any of the reducing agent, the pH adjusting agent, and at least one metal in solution.