CST has developed a new type of film for high definition mask with flatness change of the membrane stress state that is closer to zero.
The feature is as follows;
1) Pattern cross-section shape right smooth tapered with little "side-etching" so as to easily generate a sub-micron pattern.
2) Raising of particle during sputtering Reduced, and half-pinhole defect decreased by two digits in comparison to the earlier standard.
3) Flatness change before & after sputtering limited to less than 1/5 of earlier standard, and even made possible to zero.
4) Membrane composition altered to limit possibility for defects, thus being able to reduce the amount of erosion that can penetrate through scratches on the plate.
* Etching character of ZF11
* Time of additional etching and loss volume of pattern-width
ZF11; Improvement of pattern cross-section
CST establish the way of deposition, which controls pattern cross-section shape, not only to be up right sharpness but to be smooth right tapered with its angle.
There will have little effect on the cross-section shape even after adding etching time, and thus keep the best performance against "side etching".
* ZF11; SEM photo
Smallest change of flatness before and after coating ZF11
ZF11 realizes the flatness change close to almost zero with the least effect on the substrate.
Generally, Chrome film force itself to shrink compare to Chrome oxide film itself grow extend,
in such a way as to reduce the chrome stress with the balance of Chrome oxide reaction.
* Flatness change with CS8 (1220×1400×13t)
* ZF11 Flatness change with CS8 (1220×1400×13t)
* Flatness change with 800×920×8t
Conventional products have many half-pinhole while they have less pinholes. However, the result of in-house testing half-pinhole with ZF11 says that the quantity of half-pinhole over 2µm decreased by 1/10 to 1/100 ompare to the conventional film type.