Abstract: This invention relates to an on-line statistical process control device for solder paste and residues. The invention consists of electronics hardware, software, and probing systems. The electrical hardware of the invention provides voltage and current measurements of solder paste materials, the software of the invention controls the hardware, provides real-time complex, non-linear least squares curve fitting for equivalent circuit analysis, data storage and retrieval of circuit parameters and behavior, and statistical process control tracking and charting. The probing systems of the invention allows for 2, 3, and 4 probe surface and bulk measurements of the solder paste and residues.

Abstract: An impedance spectroscopy system characterizes the rheologic and thixotropic properties of solder paste and residues by measuring its impedance at various frequencies. The impedance spectroscopy system provides voltage and current inputs to a sample at various frequencies and measures the resulting impedance. The impedance spectroscopy system stores equivalent circuit parameters for multiple solder pastes and residues, controls the voltage and current inputs to the sample, displays measurement data in real-time, displays results, and notifies the operator if results exceed preset limits.

Abstract: This invention relates to an on-line statistical process control device for solder paste and residues. The invention consists of electronics hardwa software, and probing systems. The electrical hardware of the invention provides voltage and current measurements of solder paste materials, the software of the invention controls the hardware, provides real-time complex, non-linear least squares curve fitting for equivalent circuit analysis, data storage and retrieval of circuit parameters and behavior, and to statistical process control tracking and charting. The probing systems of the invention allows for 2, 3, and 4 probe surface and bulk measurements of the solder paste and residues.

Abstract: This invention relates to an on-line statistical process control device for solder paste and residues. The invention consists of electronics hardware, software, and probing systems. The electrical hardware of the invention provides voltage and current measurements of solder paste materials, the software of the invention controls the hardware, provides real-time complex, nonlinear least squares curve fitting for equivalent circuit analysis, data storage and retrieval of circuit parameters and behavior, and statistical process control tracking and charting. The probing systems of the invention allows for 2, 3, and 4 probe surface and bulk measurements of the solder paste and residues.

Abstract: A system for monitoring the soldering process which comprises a soldering ans including a means for monitoring analog heat flow, a means, connected to said soldering means, for converting analog heat flow readings into a digital temperature data points, a computing means, connected to said means for converting analog heat flow readings into digital data points, which smoothes the temperature data points; locates the beginning of the temperature data point decay; locates the beginning of the temperature data point recovery; calibrates the system for monitoring the soldering process; and classifies the current temperature data point input as an iron cleaning operation or a soldering operation.