Laboratory for Advanced Materials Processing

___________________________________________________________________________________________                 

Notes:

• Photoresist shelf life may be extended to 6months or more by keeping it refrigerated at 30-70 oF.
• In general, the hard bake temperature should be at least as high as the expected wafer temperature during later processing, especially for plasma, ion, and wet chemical etch resistance.
• Higher hard bake temperatures can also improve film adhesion.
• Exceeding the recommended hard bake temperature of 150 oC can result in deformation of the resist profile.
• The process parameters given below can change based on room temperature, humidity, and condition of the process chemicals. The given conditions are meant as a guide. If you find that the recommended values do not result in acceptable results, alert the lab manager.
• If you choose to work with P/R thicknesses other than the standard 1.4um and 4.6um processes, be aware that you will need to modify the exposure dose, soft bake time, and develop time for your particular process.

  Process Description:

  • Process Overview:

    	- Dehydrate wafers in convection oven at 120C - 150C for 30min minimum
    	- Prme wafers with HMDS for adhesion (not required)
    	- Spin photoresist (AZ 5214 or AZ 9245)
    	- Softbake
    	- Expose
    	- Post-exposure bake (not required - can be used for image reversal in AZ 5214 resist
    	- Develop (AZ 400K developer)
    	- Hard bake
    	- Strip after final processing (AZ 400T stripper)
    

  • Standard Processes:

    	Recipe 1	Recipe 2
    	2.5um thick	4.6um thick
    Photoresist:	AZ 5214	AZ 9245
    Min resolution:	< 1 um	1.4 um
    Spin speed:	4000rpm (recipe 1)	4000rpm (recipe 1)
    Softbake (oven):	80-100 oC	80-100 oC
    Softbake (hotplate):	90-110 oC	90-110 oC
    Exposure dose:	50-100 mJ/cm^2	550-1100 mJ/cm^2
    Exposure time @ 3mW/cm^2:	17sec - 34sec	3min 5sec - 6min 11sec
    Develop time:	~ 1 min	~ 5 min
    Hard bake:	120C - 150C for 30min	120C - 150C for 30min

    
    
  • Spin Charts: Note: The spin charts below are from the AZ product literature. The actual results may differ significantly, and these charts are to be used only as a general guide. The settings listed above will be updated based on lab user feedback, and represent the best estimate of actual processing conditions.
  • AZ 5214:

    spin speed (rpm)	thickness
    3000	1.63um
    4000	1.41um
    5000	1.26um
    6000	1.15um
    7000	1.01um

    
    
  • AZ 9245:

    spin speed (rpm)	thickness
    1000	10.0um
    2000	6.5um
    3000	5.2um
    3500	4.6um
    4000	4.2um
    5000	4.0um