Level, so you can solve the problem with only two levels. For most subtle problems, the important situation involves the section line, so the model is directly applicable. In other cases, such as circular holes, some symmetrical sections are like this, and the algorithm is still effective. The second main assumption is that the etching rate is a scalar function of position, regardless of the movement of the front end and the direction of local etching before history. In some practical cases, this has not been shelved. For example, polymethyl methacrylate (PMMA) found a gel region in the process of resisting the development of solvent interface, so one of the functions of etching rate is historical neighborhood and exposure. On the other hand, the second assumption is not in the so-called "preferential erosion", but that the etching gain is faster along a certain.
The crystal orientation makes the etching anisotropic.
The algorithm described here is called "string algorithm" [83]. Pre-etching simulation
A series of points are connected into a straight line to form a string. At each increment, each
Figure 4- 1 shows the point where the vertical corrosion front advances. most
The algorithm adjusts several parts to make their lengths roughly equal. other
Data input and output of etching front-end subroutine.
In developing countries, it is an important problem and algorithm to choose the appropriate standard and part length. it
It seems that the part must be too long, so any developed curve will be well defined.
In other words, there should be some adjacent parts of the maximum angle, which may be 0. 1 radian. this
However, standards have led to the spread of some fields, and the front has not expanded.
Or a contract. The elite of this algorithm tries to keep the length of roughly the same part.
The result is that the position error is about half the length. The error can be reduced.
Reducing the proportion of the average length of parts will increase the calculation time.