Focus depth

Figure 8a and b illustrate Eqs. 9 and 10, respectively. The normahzed aberration function

Inorganic resists have many advantages over conventional polymeric resists, especially in regard to resolution, linewidth control latitude, focus depth tolerance, and dry processability. These features make them very suitable for application to submicron VLSI fabrication. Efforts to improve processing technologies will open the way for practical use in LSI fabrication. 

We should not confuse depth of field with depth of focus. Depth of focus refers to the range of image plane positions at which the image can be viewed without appearing out of focus for a fixed position of the object. In other words, it is the range of screen positions in which and images can be projected in focus. The depth of focus is M2 times larger than the depth of field. 

Shrinking transistor size demands pattern definition tools that can print increasingly smaller features. However, increasing resolution for smaller features is obtained at the expense of the depth of focus. Depth of focus is the vertical range over which the image will be in acceptable focus (i.e., the image will adequately print). If the mask feature cannot be adequately imaged on... 

Entfemen von Schutzgrappen deproteinized (DP) entproteinisiert depth of focus/ depth of field... 

Fig. 26 Focusing depth dependent vertical and longitudinal voxel size, which is the origin of most observation errors. The laser was focused at different positions to produce a exactly half, b over half, and c less than half voxels, d SEM image of voxels corresponding to the situation of (a), (b) and (c)...

---