Turn COTS ICs into High-Reliability ICs

Introducing a technical paper demonstrating an internal study conducted by ISI

Addressing Market Needs to Withstand High Thermal Cycling

Many leading-edge semiconductor device packages are designed for mass-market consumer products, like smartphones, tablets, and wearable technology. While these packages are cost-effective and sufficiently capable for consumer electronics, they are inadequate for harsh environmental applications. For example, leading DDR3 and DDR4 devices are only available in chip-level packages that have demonstrated early-life solder joint failures in environments with frequent temp cycles, including aerospace and defense applications.

rugged cots components

Experimental Study Shows Improved Thermal Performance with Overmolding

ISI has developed overmolding technology which encapsulates the standard DDR3 device, in material designed to match the CTE of the host motherboard extending solder joint life by 3X over a standard component. This technology is available not just for DDR devices, but any semiconductor chip, as well as multi component modules.

We conducted an experiment to study the effects of thermal cycling on 3 different component configurations (pictured below). Our experiment subjected these configurations to 7,000 continuous one-hour cycles (from -40 C to +95 C to -40 C). The overmolded device (Configuration 3) outperformed the other 2 configurations, resulting in increased solder joint life by a factor of 3x over the standard COTS configuration (Configuration 1). Read our technical paper to learn more about the results of our experiment.

Configurations 1 & 2

rugged cots components

Config. 1: COTS Micron component (SAC302 solder balls) and Config. 2: Micron component with SAC302 balls replaced with eutectic tin/lead balls

Configuration 3

ruggedized cots components

The COTS Micron part repackaged on an interposer having the same 0.8 mm pitch, eutectic tin/lead balls, and overmolded

In addition to improved solder joint reliability, overmolding provides other benefits, including:

Solder ball crack
Failed solder joint due to thermal cycling
measured cumulative failures for each of our three component populations as a function of the number of thermal cycles
Comparative Weibull plot data for 3 configurations

Click here for a more in-depth view and to download the PDF,
COTS DRAM Modules Ruggedized with Overmolding for Improved Thermal Cycling Performance