End Test Phase of IC - Rotary Tower Sorter

Introduction to Rotary Tower Sorters

Semiconductor testing is indispensable throughout the entire semiconductor manufacturing process, from design verification to final testing. It includes design validation, process control testing, wafer testing (CP testing), and final product testing (FT testing).

Rotary tower sorters are primarily used in chip design verification and final product testing (FT) phases, serving as essential equipment in the end testing process. These sorters are particularly suitable for marking, testing, sorting, and packaging small-sized discrete semiconductor components. They are high-speed sorting machines with a main turntable at the center and multiple test stations arranged around the main motor in sequence, typically available in configurations with 12 or 36 stations.

1. Products are fed onto the main motor turntable through the feeding structure.
2. The main motor turntable picks up the chips and rotates to transfer them to the next station.
3. The feeding station operates.
4. The motor turntable picks up the next product.

Features:

- Simultaneous operation of multiple stations, reducing production cycles.

- High precision and fast speed.

- Simple installation and small footprint.

Main Turntable Motor Three Elements

The rotary tower sorter integrates multiple processes into one high-speed testing equipment. With increasingly fierce industry competition, the requirements for equipment are also rising. Capacity, downtime due to faults, and testing accuracy are the three key elements to evaluate rotary tower sorters. Therefore, the selection of the main rotating motor is crucial for ensuring both increased capacity and high yield rates during testing. Currently, the fastest devices in the industry can achieve speeds of 50-60K or even higher chip detections per hour:

- Capacity: high speed, high acceleration and deceleration, high rigidity.

- Downtime due to faults: stability.

- Testing accuracy: repeat positioning accuracy.

Conventional rotary tower test sorting machine technical requirements:

- 16-36 stations / rotation angle: 22.5°~10°

- Single station rotation time: 16~24ms

- Turntable inertia: 0.010~0.020 kg.m²

- Stop time: 35~60ms

- Capacity: 40~60 k UPH

- Average downward / upward Z-axis movement time: 6~20ms

Aistec's application solution:

Direct drive solution for main turntable

The rotation of the main turntable is one of the most critical movements in high-speed sorting machines. The driving condition of the main turntable depends on the performance of the selected main motor. Oerlikon's DD high-speed series can fully meet the motion curve requirements of rotary tower applications, particularly suitable for high-precision movement, high-speed response, and high-end requirements. From a motion control perspective, this process is highly challenging: it requires the rotary tower motor to operate at very high speeds and withstand vibrations. Equipped with Oerlikon's servo drive customized for high-speed sorting machines with direct drive motors, further enhances speed stability.