Simplify Semiconductor Wafer Handling with Modular Products from the AlphaStep AZ Series Family

What is a wafer?

A wafer is a thin, flat, and typically circular slice or substrate of a crystalline semiconductor material.  These wafers are typically made from silicon, although other materials like gallium arsenide are also used in certain applications.  Wafers serve as the foundation for manufacturing integrated circuits (ICs) and other electronic components.

These wafers need to be handled delicately and precisely to prevent damage.  Typically, wafers are handled and transported inside a wafer processor.

Motors, linear actuators, and rotary actuators from Oriental Motor's AlphaStep AZ Series product family offer universal features, drivers, and software.  All motor systems are equipped with a battery-free absolute encoder, low-loss lamination technology, and reliable Keep-in-Step technology with automatic correction.  The driver's servo-emulation mode enables high efficiency, low-noise operation where the motor uses just the right amount of current for the motion profile.

These products are modular; meaning different types of motors, actuators, and drivers can be mixed and matched according to your needs.

The simplified setup not only reduces the material costs, wiring time, and problems related to sensors but also enhances functionality without sacrificing performance.

We will go over three motion axes typically used in a wafer handling process: the loading/loading axis, the transfer process, and the alignment process.

• Compact and high strength 
  The rack and pinion design can easily convert rotary motion into linear motion.  Although the linear motion mechanism is compact, it can still lift or lower a heavy load up to 100 kg (up to 200 kg with newer LJ Series) due to its high strength design.

Operation of a rack-and-pinion system

The gear (deceleration unit) is driven by the pinion shaft of the motor, and further transmits it from the pinion gear then to the rack to convert it into linear motion.

• Quicker design and assembly
  Since the rack-and-pinion system is pre-assembled, it reduces the time needed to design (including material selection, mechanism design, and management of blueprints) and assembly.  Both ends of the rack can also be fixed in place to allow the motor to run by itself. 

Components used

① Fixed-side block ② Transportation table ③ Linear guide ④ Support-side block ⑤ Coupling case ⑥ Coupling ⑦ Fixed-side bearing ⑧ Ball screw ⑨ Support-side bearing

Due to the built-in battery-free encoder, external sensors can also be eliminated.

• High positioning accuracy 
  A high level of repetitive positioning accuracy can be achieved, which enables precse lifting and lowering of the load.
  
  Vertical operation is also simple. A model equipped with an electromagnetic brake is also available as a fall prevention measure.

Repetitive positioning accuracy (reference value)

This is the actual measurement value with a transportable mass. It will vary depending on the load, driving conditions, and mounting direction.

• Easy unit setting
  By using the universal MEXE02 support software, the travel amount can be set easily in millimeter units instead of steps or degrees.

Minimum step angle

High-Speed Type: 0.01 mm
Large Transportable Mass Type: 0.001 mm

Operating speed range

0~500 mm/s (High-speed type)
0~90 mm/s (60 mm frame size for large transportable mass type)
0~40 mm/s (80 mm frame size for large transportable mass type)

• Homing without external sensors 
  The αSTEP AZ Series is equipped with a battery-free mechanical absolute encoder at the rear of the motor, which enables high speed sensorless homing operation.  It will also protect against the effects of any external sensor malfunctions.

• High accuracy/non-backlash
  Unlike other gearheads, a harmonic gearhead provides backlash-free positioning accuracy.  The harmonic gear has many teeth in simultaneous meshing engagement, and it is designed to average out the effects of tooth pitch error and cumulative pitch error to ensure high positioning accuracy (0.025˚ to 0.017˚ depending on size).

• Geared type for high inertia
  The AZ series includes various geared types and gear ratios designed to handle high inertia loads effectively. This ensures that wafers can be transported safely and precisely.

• Integration and downsizing 
  Oriental Motor’s geared motors do not require couplings as the teeth are cut directly on the motor's shaft, and therefore they are shorter in length.

• Precise and responsive
  These compact cylinders are highly responsive and reliable due to the built-in AlphaStep closed-loop technology, making them ideal for wafer handling tasks.  Notably, they are tuning-free, further simplifying setup.

Ball screw type:
ground or rolled

Minimum Step Angle:
0.001 mm

Repetitive Positioning Accuracy:
Ground Ball Screw: ±0.003 mm
Rolled Ball Screw: ±0.01 mm

• Easily synchronize motion
  A multi-axis driver allows for easy synchronous motion, streamlining the control system and improving operational efficiency.

4-axis EtherCAT-compatible controller

Consolidate:

• Main power supply cable
• Control power supply cable
• Communication cable
• Motor cables

• Compact design
  Because connecting parts such as linear guides and couplings are no longer necessary, the equipment as a whole can be made smaller. The number of required parts is also significantly smaller compared to self-made mechanisms.

• 4 mounting methods 
  With various mounting methods available, allowing for flexible mounting options to suit small spaces.  Through multiple combinations, an XYZ unit can be configured to create compact equipment.

• Unified Wiring

• Unified Control

• Unified Maintenance