data = {"voltage":[0]*len(size),"current":[0]*len(size),"resistance":[0]*len(size),"sheet":[0]*len(size),"size":[0]*len(size)}
ilow, ihigh, istep, compliance = -0.005,0.005,5e-4,7
## Get the current and measure the voltage
current = pa.sourceSelect(ilow,ihigh,istep,compliance)
## Start the actual measurement
i = 0
raw_input("Start Measurement: Probe Structure (enter)")
while i < len(squares):
voltage = pa.measureData()
## Calculate the derivitive with ndfit
resistance = ndfit.derivative(voltage,current)
## set the results into the dict. Using SET rather than append
## avoids complications with the redo loop
data["voltage"][i]=voltage
data["current"][i]=current
data["resistance"][i]=sum(resistance)/len(resistance)
data["sheet"][i]=(sum(resistance)/len(resistance)/squares[i])
data["size"][i]=("%sum x %sum"%(str(size[i]),str(width[i])))
c = raw_input("Probe Strucute. Press (r) for redo (enter) to continue:")
if (c == 'r'):
i-=1
i+=1
## Print the sheet resistance
import ndfit import numpy as np import matplotlib.pyplot as plt # NDFIT has support for basic math on lists built in x = list(np.linspace(-10,10,101)) y = [i*i*i for i in x] z = ndfit.derivative(y,x) print z plt.plot(x,z) plt.plot(x,y) plt.show()
"size": [0] * len(size)
}
ilow, ihigh, istep, compliance = -0.005, 0.005, 5e-4, 7
## Get the current and measure the voltage
current = pa.sourceSelect(ilow, ihigh, istep, compliance)
## Start the actual measurement
i = 0
raw_input("Start Measurement: Probe Structure (enter)")
while i < len(squares):
voltage = pa.measureData()
## Calculate the derivitive with ndfit
resistance = ndfit.derivative(voltage, current)
## set the results into the dict. Using SET rather than append
## avoids complications with the redo loop
data["voltage"][i] = voltage
data["current"][i] = current
data["resistance"][i] = sum(resistance) / len(resistance)
data["sheet"][i] = (sum(resistance) / len(resistance) / squares[i])
data["size"][i] = ("%sum x %sum" % (str(size[i]), str(width[i])))
c = raw_input("Probe Strucute. Press (r) for redo (enter) to continue:")
if (c == 'r'):
i -= 1
i += 1
## Print the sheet resistance
pa = hp_4145B(GPIB)
pa.channelDefinition()
## Sweep Vd from 0V to 1.1V
Vd = pa.sweepVoltage(0.0, 1.0, 0.05, "40E-3")
fig = plt.figure(figsize=(10, 8))
ax1 = fig.add_axes([0.1, 0.1, 0.70, 0.8])
ax2 = ax1.twinx()
for n, vg in enumerate(vgx):
# time.sleep(1)
pa.stepVoltage(vg, 0.0, 1, "30E-3")
pa.setOutput()
pa.measureData()
Id = pa.getDataIdVd()
g0 = [xx / w for xx in list(ndfit.derivative(Id, Vd))]
print "%s %f" % ("Vg =", vg)
c = cm.cool(float(n) / len(vgx), 1)
ax1.plot(Vd, Id, color=c)
ax2.plot(Vd, g0, color=c, linestyle='--')
ax1.set_ylim(0.0, max(Id) + 0.001)
ax2.set_ylim(0.0, max(g0) + 100)
ax1.set_xlabel(r"Drain Voltage $(V_d)$")
ax1.set_ylabel(r"Drain Current $(I_d)$")
ax2.set_ylabel(r"Output Conductance $(g_0)$")
## Fancy Colorbar
cmap = mpl.cm.cool
pa = hp_4145B(GPIB)
pa.channelDefinition()
## Sweep Vd from 0V to 1.1V
Vd = pa.sweepVoltage(0.0,1.0,0.05,"40E-3")
fig = plt.figure(figsize=(10,8))
ax1 = fig.add_axes([0.1, 0.1, 0.70, 0.8])
ax2 = ax1.twinx()
for n,vg in enumerate(vgx):
# time.sleep(1)
pa.stepVoltage(vg,0.0,1,"30E-3")
pa.setOutput()
pa.measureData()
Id = pa.getDataIdVd()
g0 = [xx/w for xx in list(ndfit.derivative(Id,Vd))]
print "%s %f"%("Vg =", vg)
c = cm.cool(float(n)/len(vgx),1)
ax1.plot(Vd, Id,color=c)
ax2.plot(Vd, g0,color=c,linestyle='--')
ax1.set_ylim(0.0, max(Id)+0.001)
ax2.set_ylim(0.0, max(g0)+100)
ax1.set_xlabel(r"Drain Voltage $(V_d)$")
ax1.set_ylabel(r"Drain Current $(I_d)$")
ax2.set_ylabel(r"Output Conductance $(g_0)$")
## Fancy Colorbar
cmap = mpl.cm.cool
def _partialy(Z, Y):
return np.array([
ndfit.derivative(list(Z[:, i]), list(Y[:, i])) for i in range(len(Z))
]).T
def _partialx(Z, X):
return np.array([
ndfit.derivative(list(Z[i, :]), list(X[i, :])) for i in range(len(Z))
])