Issue link: https://iconnect007.uberflip.com/i/1511625
20 PCB007 MAGAZINE I NOVEMBER 2023 Some of the concepts which we oen con- sider for new frame implementations or exist- ing tooling upgrades include: • Making the 2D codes on every layer offset, and thus readable in panel form by X-ray. • Eight-point tooling for non-linear analysis. • Use of clearances for fiducials instead of pads on X-ray coupons to avoid clearing out of Cu layers which can lead to lamina- tion voids. • Adding enough positions for sequential lamination tooling to avoid ever using the same tooling twice. • Reducing legacy coupon sizes. Hack: Normalization to zero of layup alignment fiducials One popular hack for improving alignment accuracy is to compensate the targets for pre- dictable process variation. is is commonly done on post-lam targets (global lamination scaling is applied), but not commonly done on post-etch/pre-lam targets (normally output without scale). It was discovered years ago that removing the scaling from post-etch targets made it easier for the post-etch tooling equip- ment to best fit since the deviations which needed to be compensated for were less. As an extension of this design practice, we also find that by taking the data from the post-etch tool- ing or layup operation, a model can be built which provides a post-etch scale-compensa- tion factor to account for the movement which occurs from etching the pattern. is further reduces the need for compensation and makes the subsequent compensation errors less. Manufacturing Compensation Factors Ma n u f a c tu r i ng c o m p e n s a t i o n f a c to r s include modeled etch comp, modeled plat-