I am sorry your baby has this trouble.
It is called Ear margin dermatitis and can be hereditary in Doxies
How to treat
TREATMENT OF EAR MARGIN SEBORRHEA
Rarely is there a cure for Seborrheic diseases, so treatment often centers on controlling the symptoms which includes the buildup of scales, crusts, plugs and excess oil on the ears and other body areas. Medicated shampoos such as Allerseb, T-lux or benzoyl-peroxide based products among others are very good at cleansing the skin. Antibiotics and cortisone are used in cases where infection and inflammation has become apparent. Retin-A, Vitamin A, Zinc, Fatty Acid supplements and several other drugs may have applications in various forms and secondary problems of the disease that occur.**
I hope your baby feels better very soon.
Warmest best wishes,