Doses

125 kV

	Si	InAsUC	InPUC	GaAsUC	SiGe
A2	1000	700	?	?	?
A4	1000	700	?	630	?
A6	1200	?	?	760	?
El6	?	?	?	?	?
El9	?	?	?	420	?
CSAR4	430	?	?	?	?
CSAR9	?	?	?	?	?
CSAR13	450	?	?	350	?
50k+A4	?	?	?	745	?

100 kV

	Si	InAsUC	InPUC	GaAsUC	SiGe
A2	900	?	300	?	?
A4	900	?	500	630	?
A6	1000	?	?	670	?
El6	?	?	?	?	?
El9	?	?	?	?	?
CSAR4	400	?	?	?	?
CSAR9	?	?	?	?	?
CSAR13	?	?	?	?	?
50k+A4	?	?	?	630	?

• GaAs: Uniform clearing
• InP: Uniform clearing
• InAs: Uniform clearing
• Si: Optimal contrast

Note

Base dose does not change with resist thickness, developing time does. However, if the developing time is fixed, say to 60s, a thinner layer of resist will need lower "base dose", since it's being over developed.

Experimental

• Dose density matrix for small and large spot size.
• Measure CD as a function of dose and density for the two spot sizes.
• Intersection of the two plots, for a given density gives isofocal dose.
• Convert doses to dose factors, given that 0% isodose == PEC_df _0%
• Base dose == isofocal dose _0% / PEC_df _0%
• For density larger than 0%, predicted dose factor = (1+η)/(1+η*ρ*(1+φ/100))
  • 1+η = PEC_df _0%
  • Fit experimental isofocal dose factors and predicted dose factor by varying psi

125 kV:

InP: 607 uC/cm2 and phi = 35%

InAs:

Si: 906 uC/cm2 and phi = 45%

GaAs:752 uC/cm2 and phi = 39%

125 kV

	Si (μC/cm2) / φ	InAs (μC/cm2) / φ	InP (μC/cm2) / φ	GaAs (μC/cm2) / φ	SiGe (μC/cm2) / φ
A2	?	?	?	?	?
A4	906/ 45%	?	607/ 35%	752/ 39%	?
A6	?	?	?	?	?
El6	?	?	?	?	?
El9	?	?	?	?	?
CSAR4	?	?	?	?	?
CSAR9	?	?	?	?	?
CSAR13	?	?	?	?	?
50k+A4	?	?	?	?	?