In [1]:

```
# Given that
F = 4e-6 # Maximum feature dimension in meter
t = 5e-6 # Photorist thickness in meter
g = 25e-6 # Allowable gap between the mask and the resist meter
lamda = (F**2)/(t+g)
print "Maximum allowable wavelength of the exposing light = %d nm"%(lamda*(10**9))
```

In [2]:

```
from __future__ import division
from math import exp
# Given that
d = 5 # Diameter of hole in micro meter
h = 100 # Depth of hole in micro meter
t = 31.58*(d*(exp(h/(60*d))-1))
print "Time required to machine the hole = %0.1f min"%(t)
```

In [3]:

```
from math import sqrt
# Given that
J = 2 # The threshold value of dose in kJ/cm**3
h = 300 # Height in micro meter
J_o = J*(exp(0.1*sqrt(h)))
print "The minimum level of exposure of the PMMA surface = %0.1f kJ/cm**3"%(J_o)
```