Precisely Resistance Control Technology Of The Chemically Integrated Nickel-based Resistor For The Printed Circuit

With the applications of 5G communication technology and the rapid increase of high-speed and high-performance electronic products,the development trend of Printed circuit boards(PCBs)tends to be small,easy package,high-frequency and high-speed characteristics.The mounting of traditional passive components on the PCB surface increases the number of pads,the surface areas of PCB and increases the parasitic effects between the pads,resulting in unstable signal transmission in high frequency.Therefore,the embedded technology to achieve integration of passive devices such as resistors instead of conventional discrete mount surface has become an important method to solve this problem.However,the current integrated resistance formed by the etching method has more than 20% error,which is difficult to meet the requirement of 5G communication error within 10%.On-line monitoring integrated resistor technology for printed circuit are proposed according to the issues above.The resistance deposition area and the resistance monitoring area are designed in the PCBs.The standard resistance value in the resistance monitoring area is monitored to control the resistance value in the resistor deposition area under electroless Ni-P plating to form the integrated resistors.This article discusses the influence of the output current of monitoring equipment on the integrated resistors value under on-line monitoring process and establishes the relationship formula between the monitored standard resistors value and the deposited resistors value.The results show that integrated resistors error in resistance deposition area is 10% when the output current is0.1 m A under on-line monitoring Ni-P embedded resistor manufacturing.It meets the performance requirements of integrated resistors for 5G communication base stations.The relationship between the standard resistors value and the deposited resistors value provides a system of standard resistors value control target deposition resistors value.The production methods and factors of integrated resistors such as development and film removal are studied.This paper studies the effects of different sizes and different patterns on value of integrated resistor technology for printed circuits.The results show that integrated resistors are designed for different sizes with a line width of 0.5 cm and a line length of 3cm,4cm,and 5cm,and the maximum resistance error is 2.9%,6.1%,and5.1%,respectively.Integrated resistors are designed for different sizes with a line length of 3 cm and a line width of 0.1 cm,0.25 cm,0.5 cm,0.75 cm,and 1 cm,and the maximum resistance errors are 8.8%,3.9%,2.9%,5.8% and 7.0%,respectively.The resistance errors of different patterns such as linear,serpentine and zigzag integrated resistors are2.9%,5.1% and 3.4%,respectively.The resistance error is within 10% to achieve monitorability and monitoring stability.The alkaline stripping solution and weak alkaline developing solution will corrode the activated palladium with catalytic center on the substrate,resulting in the resistance value is too large under the same monitoring voltage.But the resistance value errors are 7.8%,6.1%,respectively.The resistance error is controlled within 10%.Both production method show the integrated resistor has the stability,monitorability and applicability good points.The environmental reliability and thermal performance of on-line monitoring integrated resistors are analyzed.The integrated resistors are analyzed by lamination,thermal shock and hot and cold cycle.The results show that the integrated resistor has the advantages of good bonding force with prepreg,good heat resistance stability,and environment stability.