Description 

 

? Negative Resist NR71-250P is a negative tone photoresist designed for 366 nm 

wavelength exposure using tools such as wafer steppers, scanning projection aligners, 

proximity printers contact printers. 

? These are the advantages of NR71-250P over other resists: - superior resolution capability of less than 0.5 μm - fast develop time - fast photospeed - superior temperature resistance of up to 180°C - superior ivity in RIE process -     elimination of a need for application of adhesion promoters such as HMDS - shelf life exceeding 3 years at room temperature storage. 

? The formulation processing of NR71-250P were designed with regard to occupational 

environmental safety. The principal solvent in NR71-250P is gamma butyrolactone 

development of NR71-250P is accomplished in a basic water solution. 

 

Properties 

 

    ?    Solids content (%)                                                                                    9-12                          

    ?    Principal solvent                                                                                       gamma butyrolactone 

    ?    Appearance                                                                                              light yellow liquid 

    ?    Coating characteristic                                                                               very uniform,            

                                                                                                                            striation free 

    ?    Film thickness after 150°C hotplate bake for 60 s (nm)

           Coating spin speed, 40 s spin (rpm):                                                          

             800                                                                                                         400-600      

3000                                                                                                   220-280 

 

    ?    Sensitivity at 365 nm exposure wavelength (mJ/cm2 for 1 μm thick film) 21 

    ?    Guaranteed shelf life at 25°C storage (years)                                          3  

Processing 

 

1. Application of resist by spin coating at ed spin speed for 40 s. 

 

2. 150°C hotplate bake for 60 s. (softbake). 

 

3. Resist exposure with a tool emitting 365 nm wavelength. 

 

4. 100°C hotplate bake for 60 s. (post-exposure bake). 

 

5. Resist development in Resist Developer RD6/water 3:1 by spray or immersion. 

Development time for 0.25 μm thick film, for example is 30 s. 

 

6. Resist rinse in deionized water until water resistivity reaches prescribed limit. 

 

7. Drying of resist. 

 

8. In applications NR71-250P pattern becomes a part of device structure, two different 

bake processes are recommended to render NR71-250P pattern insoluble in common 

solvents: 

 

8.1.  140°C oven bake for 12 hours. 

 

8.2.  250°C hotplate bake for 10 minutes. 

 

9. Removal of resist in Resist Remover RR41 at 110°C if procedure requires it. 

 

The above procedure refers to substrates which are good conductors of heat such as 

Si, GaAs, InP, etc.  

 

 

Hling Precautions 

 

Negative Resist NR71-250P is a combustible liquid. Hle it with care. Keep it away heat, 

sparks flames. Use adequate ventilation. It may be harmful if swallowed or touched. 

Avoid contact with liquid, vapor or spray mist. Wear chemical goggles, rubber gloves  

protective coating.