MA8 Aligner

The MA8 is very new tool. Because the tool is very new, user interface is easy and straight forward. 

Initialization

• double click the icon at the desktop 

• click "initialization" button when you enter the home page.

Replace mask holder

• "change tools"

• At the page of Change Tools, click "Clamp Mask Holder" and get it off. Take the mask holder outside the machine.
  At the most, the mask holder is already outside the machine after the prior user. That's good. 

• disconnect hose connector

• replace the mask holder
  Dr. Hall group usually use 4 inch wafer. That will be a 5-inch mask holder and 4-inch wafer chuck.

• connect hose connecter

Install photomask

• Put the mask holder in the trail. That way is convenient for you install mask.

• Install photomask to mask holder. Note that the clamp should be touching mask tightly. 

• "Mask vacuum "

• Left hand is to flip the mask holder. Use right hand to cover the photomask in case the vacuum is not good and the mask drops.

• Insert mask holder into machine. 

The tool will ask you to remove wafer from chuck and close the lid. Then, the tool will run self calibration. This is the goodness. For the old aligners, like EVG620 or MA6, we don't really know the UV light intensity for each exposure. Xiaoyu experienced the EVG620's story. EVG620 is using a UV light bulb as a source. When Xiaoyu needs to use the tool, Xiaoyu has to measure the UV intensity by himself. And then he calculate the exposure time based the time-varying UV intensity. That was painful.  

Load wafer

• "start process" at the home page

• install chuck and wafer 

• Gently push the chuck into machine.
  Otherwise, the wafer is easily run on the nails. In that case, the wafer is not perfectly parallels to photomask. Wedge Error Compensation process will report some errors.

Alignment

• Adjust joystick to align mask and wafer.
  Usually, we don't need to run alignment for single-mask photolithography. Dr. Hall group usually run Backside Alignment on an SOI wafer. During that case, we need to run the recipe of Backside Aligment (BSA) from the beginning. 

Exposure

• "exposure"

Unload wafer

Unload mask

• "change tool" at the home page 

• "clamp mask holder"

• Flip and place the mask holder in the trail of the machine
  This is same as what you install mask.

• "mask vacuum"

• remove your mask via adjusting the clamp on the holder. 

• You are good to go:)