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64 PCB007 MAGAZINE I MARCH 2021 a Gauge R&R study, all under the auspices of IPC. e work will build on the approach in TM-2.6.3.7 but will tailor the approach ap- propriately for the two technology areas. TM- 2.6.3.7 will also be updated from the current 2007 version, with incorporation of the new B53 pattern which incorporates a 200 µm SIR pitch pattern. e new standard will also look at test duration, which will include an option to test for at least 500 hours and possibly be- yond 1,000 hours. e cleaning efficacy SIR evaluation, and the corrosion of solder masks, will follow a simi- lar path, with the development of test vehicles, dummy components, and a test protocol. e IPC SIR committee 5-32b will lead the devel- opment of the documents and organise a round robin trial with Gauge R&R validation. Funding e standards will be written as now with- in 5-32b, by voluntary work. Production of the samples might be funded by IPC, and then the intercomparison work by the collaborators will take place at their expense. Methodology For these we need a consensus on the track and gap for the patterns. Our current point is 25 V/mm, with the 200 µm (B53) and 500 µm (B24) patterns. For the low voltage application, it is envisaged that the test voltage of 2V and ~50 µm track spacing, and this will lead to 40 V/mm. With high voltage testing an anticipated field strength of 500 V/mm is expected, hence with a 1000V test the feature spacing will be 1 mm. It has been demonstrated that electrochemi- cal processes will not always scale with feature size, or SIR pattern pitch, and the applied volt- age. Hence, careful consideration must be giv- en to the applied test, and the conditions of the test must be applicable to the use case. If not, the produced data can be valueless. erefore, new test coupons will be required and the in- put from the wider industry is essential to de- fine the requirements. New material systems are known to have a long incubation period before the onset of cor- rosion; periods of up to 500 hours have been noted. Testing at >1000V may generate failure modes that occur over relatively long distanc- es and hence may take even longer times, test durations of over 1,000 hours may be required. Proposals for the cleaning efficacy SIR evalu- ation and the corrosion of solder masks will be brought forward. Validation When the committee agrees, the test meth- odology, the method, and chosen test vehicles need to be validated. Previously an intercom- parison was organised jointly by IPC and the IEC, and the results were reported and pub- lished as IEC TR 61189-5506. is report com- pared the response using SIR patterns with 500 µm, 318 µm and 200 µm conductor separation. e test coupon used for this was IPC B53 Rev A. ese results are now an important part of the updating of TM-2.6.3.7. e development work described here plans a similar exercise with the to-be-developed standards and test vehicles. Work has already started and there is a Rev B to IPC B53, the development of which was in- tended as a potential replacement for IPC B24, B25 and B25A coupons. A further refinement of the B53 to the B55 has also been designed which contains an extra pair of patterns with 50-µm spacing. Both of these new boards are shown in Figures 1 and 2. e plan is to start this work imminently and produce the necessary dra standards and test vehicles. An A team would be formed, and it is anticipated that this may include the following partners: • GEN3: UK—Graham Naisbitt and Dr. Chris Hunt • Electrolube: UK—Phil Kinner • Precision Analytical Laboratories; Kokomo, USA—Joe Russeau • Magnalytix: USA—Mike Bixenman