Filter optimization for X-ray inspection of surface-mounted ICs

被引：8

作者：

Blish, RC ^{[1
]}

Li, SX ^{[1
]}

Lehtonen, D ^{[1
]}

机构：

[1] Adv Micro Devices Inc, Sunnyvale, CA 94088 USA

来源：

40TH ANNUAL PROCEEDINGS: INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM | 2002年

关键词：

D O I：

10.1109/RELPHY.2002.996666

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

A thin Zn filter (similar to20 mum) and relatively low X-ray tube voltage (similar to45 KV) is recommended for X-ray inspection of surface-mounted device solder joints on printed wiring boards (PWB). An optimal filter minimizes the Si dose that could result in cumulative damage to sensitive IC circuit nodes, yet provides good contrast for metals such as Cu traces on PWB and device solder balls. While we expect orders of magnitude Si dose reductions when effective filters are inserted, a properly chosen filter should not attenuate the portion of the white X-ray spectrum required to image Cu, Sn and Pb (solder balls). Some X-ray inspection suppliers can achieve a Si dose of as little as 0.060 Rads; while other X-ray inspection suppliers, not yet optimized for minimum dose, may use as much as four orders of magnitude more dose. We used Thermo Luminescent Detectors (TLDs) to measure the X-ray dose that IC product shipments would encounter during a shipping process (personal baggage or cargo) as minimal (less than or equal to0.050 Rads).

引用

页码：377 / 379

页数：3