Patent ID: 8341587

Claim:
A method of managing process factors that influence electrical properties of printed circuit boards (PCBs), comprising: obtaining measurements of at least one type of electrical property of N number of PCBs by a computing device, wherein N is a positive integer; analyzing the measurements to obtain characteristic values from the measurements by the computing device; selecting n process factors that influence the electrical property by the computing device, wherein n is a positive integer; computing a maximum value and a minimum value for each of the n process factors by the computing device according to a corresponding middle value of each process factor using a predetermined variation percent; designing first experiments for the n process factors using the Taguchi method, substituting the maximum value, the middle value, and the minimum value of each process factor into the first experiments, and computing a simulated result of the electrical property of each of the first experiments by the computing device; computing an average simulated result of each of the maximum value, the middle value, and the minimum value of each process factor by the computing device; computing a variation range of the average simulated results of the maximum value, the middle value, and the minimum value of each process factor, and putting the n process factors into an order according to the variation ranges by the computing device; determining m process factors which have important influence to the electrical property from the n process factors according to the order, wherein m is a positive integer by the computing device; designing second experiments for the m process factors using the Response surface methodology (RSM), substituting the maximum value, the middle value, and the minimum value of each of the m process factors, and the middle value of each of the other (n−m) process factors into the second experiments, and computing a simulated result of the electrical property of each of the second experiments by the computing device; fitting a computing formula for the electrical property using the m process factors by the computing device, according to the second experiments and the simulated results of the electrical property of the second experiments; and substituting the characteristic values into the computing formula by the computing device, to compute a variation range of each of the m process factors.