small typo

Author: damiano-flex

tidy3d/components/tcad/effective_DOS.py

@@ -122,7 +122,7 @@ def calc_eff_dos_derivative(self, T: float):
 
 
 class DualValleyEffectiveDOS(EffectiveDOS):
-    """Effective density of states model that assumes combibation of light holes and heavy holes with isotropic effective masses.
+    """Effective density of states model that assumes combination of light holes and heavy holes with isotropic effective masses.
     The model assumes the standard equation for the 3D semiconductor with parabolic energy dispersion:
 
     .. math::