Circuit under pad (CUP) is required (also called bond over active circuitry (BOAC)). Copper (Cu) wirebond needs to replace gold (Au) wirebond for lower cost. Pad cracks are a primary concern in this development because cracks mechanically weaken the bond and may cause leakage or shorts between CUP electrical nodes.

• Bond-over-active-circuitry (BOAC), 2 –7 levels of metal • Maximum pad design flexibility for small die size, • Interconnect circuitry in all levels below the pad metal, (& ESD protection) • “pad anywhere” is desirable • Up to 6 wafer probe touchdowns • Cu wirebond to replace Au wirebond • Higher reliability

Jan 1, 2011 · The resulting bond pad structures effectively address BOAC pad reliability concerns, permitting Au or Cu wire bonding on relatively thin top metal. Cu wire bond is attractive on BOAC designs for lower cost than Au wire, while improving the thermal capability of …

In addition, pads having bond over active circuitry (BOAC) which are much more sensitive to pad cracks, are likely present in the same IC. Cracks in the pad dielectric weaken the bond reliability and may cause electrical leakage or shorts to circuitry under the pad.

The need for more robust bond pads Product needs: • bond‐over‐active‐circuitry (BOAC) • maximum pad design flexibility for small die size, “pad anywhere” • 2 – 7 levels of metal • interconnect circuitry in all levels below the pad metal, (& ESD protection)

Circuit under pad (CUP) is required (also called bond over active circuitry (BOAC)). Copper (Cu) wirebond needs to replace gold (Au) wirebond for lower cost. Pad cracks are a primary concern in this development because cracks mechanically weaken the bond and may cause leakage or shorts between CUP electrical nodes.

In this work we report how the design of the BOAC circuitry in a pad can help to achieve these objectives simultaneously. Traditional pad structures consist of sheets of metallization across the pad window in all metal levels, connected to the pad metal by via arrays.

Explore IC bond pad structure and circuit under pad (CUP) development, wafer probing, wire bonding, and reliability improvements. Study lib Documents Flashcards Chrome extension

Mar 1, 2008 · This work evaluates the wire bondability and the reliability test for the stacked-die TFBGA packaging with the Sn–4.0Ag–0.5Cu solder ball. The BOAC pad is the top die structure and the normal pad is the bottom die. Both test chips are low-K …

Apr 24, 2012 · PAD的结构牵涉到一些design rule,多在design manual里都有描述。当前先进工艺下PAD一般是ME1+VI1+... TOPMETAL+...+AL+PAD(or PASV)依次连接叠加而成。 其中有一种BOAC PAD(bonding on active circuit )因PAD下面可以摆放电路(多是ESD)，会拿掉较低的某些metal。 还有一种RF PAD下面的PWELL会被 ...