Development Of PI - Type Thick Film Resistive Attenuator

This topic mainly study on how to research and produce a shapeπattenuator, resistor network type by fabrication technology for chip thick film resistor, which is consisted of three resistors based on current thick film resistor production line. This attenuator contains two resistors on same resistance value, three terminations which one is on, and another two is off.Depend on the construction and main technology parameter of this attenuator, firstly we select a substrate for type 2012 in order to proof that we can research and produce this attenuator by a ways of printing two resistance values of resistor once, trimming resistance value three times and manual coating. We made a set of anode figures used in screening, manual coating and a simple probe card depended on substrate size and design configuration, and finally, we researched and produced this attenuator, 5dB,RNA2012 type, shapeπ, thick film resistor type. This attenuator is difficult to realize mass process and technology controlling but can by manual, because there is off on coating on one side of attenuator.So we found a type 1616 substrate with two holes in market which can cut one side to coating, and can link other side by connection design of back electrode, finally, we produced the attenuator, 5dB,type RNA1616π, thick film resistor type same to type RNA2012π. In order to research and produce 1dB∽10dB attenuators, we still need to adapt a way to print resistance value twice.Because this way applies to the attenuator which resistance value rate is 1:6, i.e. the attenuator of its decrement more than 5dB. With researching and producing to the two types, we finally determined the high reliability and technology flowchart applied to mass process in current thick film resistor production line. By selecting substrate, type 1616π, a way of printing resistance value twice and laser trimming three times, we can produce this attenuator, thick film resistor, type RNA1616π.The innovate points of this topic is integrated new construction and appearance design, L-shape and J-shape trimming figures, and the new points also lie in sintering to two resistance value, good bridging to resistor body and electrode to ensure its high reliability, good packaging to II glass, and the location of laser groove far away substrate groove.Finally, we performed resistance value testing, thermal shock, resistance-temperature characteristics. We detected its decrement, voltage standing wave and input impedance of the attenuator by microwave network analysis tester, type 37369D in accordance with"verifying procedure of resistor's attenuator"in GJB2214-94.