FormFactor Introduces Probe Card Family For Wire Bond SoC Devices
As the functionality and complexity of wire bond logic devices continue to rise, the number of I/Os per device is increasing. With semiconductor dimensions continuing to shrink, more of these I/Os are being packed into a smaller area. By supporting pad pitches down to 40 microns, FormFactor's TrueScale PP40 probe card allows IC manufacturers to shrink the size of their test pads — enabling some customers to retain a single-row pad layout, which provides better wire bond tool uptime and efficiency.
Traditional vertical probe solutions struggle to support wafer-level testing at these smaller dimensions. Conventional cantilever probing solutions require frequent maintenance — often multiple times per day — to ensure proper alignment with the test pads, which limits test cell uptime and efficiency. With the requirement for higher parallelism, the limitations of these conventional solutions are exacerbated, making efficient high parallelism testing challenging and potentially unattainable.
In contrast, the TrueScale PP40 product leverages FormFactor's proprietary MicroSpring technology to enable 40 micron pitch probing with multiple thousands of contacts. It provides excellent positional accuracy over the life of the probe card (designed to support greater than a million touchdowns), and enables small pad sizes. In normal usage, the TrueScale design requires minimal maintenance with no spring positioning adjustment and less frequent cleaning than conventional technologies. These capabilities are essential for the cost-effective testing of consumer devices, which can have production rates of millions of units. In addition, the TrueScale PP40 probe card has proven scrub capabilities, for more robust electrical contact. FormFactor's MicroSpring contacts are designed to penetrate the tough oxide layer on top of aluminum test pads in order to achieve optimal electrical contact — providing better test results and reducing false test failures, which can improve yields.
Another advantage of the TrueScale technology is its ability to leverage multi-site testing, to take better advantage of the latest high pin count advanced test equipment (ATE, >2000 I/Os). With its scalable MEMs design, TrueScale expands parallelism to the ATE's limit, allowing the testing of 8 to 16 devices in parallel, compared to 2-4 devices with conventional probing technology. At the same time, the MicroSpring contact design provides low contact force to allow reliable probing on pads designed over active device areas.
"As wire bond logic manufacturers ramp up volume to meet growing demand for mobile and wireless applications, they need wafer-level test solutions that can scale with their requirements," stated Stefan Zschiegner, vice president and general manager of FormFactor's SoC Product Business Group. "Advanced MEMs-based probe card solutions like our TrueScale product family enable the higher parallelism and tighter pitch requirements our customers need. The ability of FormFactor's TrueScale PP40 probe card to enable low, consistent contact resistance with minimal cleaning, even after thousands of touchdowns, can help customers maintain high yields with better throughput to lower their cost of test."
FormFactor is now taking orders for the TrueScale PP40 wafer probe card.
SOURCE: FormFactor