Nanoflow Slit Rheometer Summary


1. Overview

Nanoflow slit rheometer is designed to measure the viscosity of thermoset polymers where the viscosity changes rapidly with time (such as epoxy molding compounds used in semiconductor-chip encapsulation). Unlike traditional viscometers, the Nanoflow rheometer can measure the viscosity at the actual processing ranges. Several tests using this rheometer show that the viscosity measured with this instrument is much more accurate than that from traditional rheometers.

2. Advantages of the Nanoflow Slit Rheometer


3. Verification of the Nanoflow Slit Rheometer


4. Comparison with Other Rheometers

Parallel-Plate Viscometer
  • The viscosity is measured at low shear rates and low temperatures. To use this data for chip encapsulation analysis, the measured data have to be extrapolated to high shear rates and high temperatures. This extrapolation can lead to significant errors.
  • For the spiral-flow cases tested so far, the calculated results using the parallel-plate data differed from the experimental results by 100 to 400%.
  • Paddle-shift calculated using the parallel-plate rheometer viscosity data differed from the experimental results by about 800% for a test case.
Spiral-Flow Test Rheometer (RPA)
  • The distribution of temperature, shear rate and cure is not uniform, and temperature and shear rate change during testing. This makes it difficult to measure the viscosity accurately.
  • The parameters related to the viscosity dependence on temperature, shear rate and cure have to be determined inversely by numerical simulation. This can cause errors.
Shimadzu Flow Tester
  • The distribution of temperature, shear rate and cure is not uniform, and temperature and shear rate change during testing.
  • Almost no curing takes place in the capillary during testing. Because of this, determination of cure dependence of viscosity is impossible with this instrument.

5. Services

  • The first service is that Nanoflow provides the total package to the customer. The package includes the rheometer hardware, software (for rheometer control, data acquisition and data reduction), installation, training and 1 year warranty. ST-30 model can be used as a transfer molding machine for chip encapsulation as well as a slit rheometer. SR-30 model can only be used as a slit rheometer.
  • The second service is that Nanoflow helps the customers to build their own slit rheometer. This can be an economical choice especially if the custometer already has, for example, a servo-motor controlled transfer molding machine. They can modify their transfer molding machine to a rheometer. Nanoflow will license the slit rheometer technology to the customer. Also Nanoflow provides software, design and consulting.
  • The last service is that the customer simply provides transfer molding machine and Nanoflow will do all the works to transform the transfer molding machine to a slit rheometer (such as design, part manufacturing, testing).