Single crystal furnace thermal field and single crystal furnace

The invention relates to a single crystal furnace thermal field and a single crystal furnace. The single crystal furnace thermal field comprises a furnace bottom assembly and a heat preservation cylinder assembly, the furnace bottom assembly comprises a furnace bottom curing felt and an annular base plate, a round boss and an annular boss which are coaxial are arranged on the upper side of the furnace bottom curing felt in a protruding mode, the inner diameter of the annular boss is larger than the outer diameter of the round boss, and the base plate is coaxially arranged between the round boss and the annular boss in a sleeved mode. The outer diameter of the base plate is equal to the inner diameter of the annular boss; the heat preservation cylinder assembly comprises a heat preservation cylinder and a felt fixing cylinder covering the peripheral wall of the heat preservation cylinder, the bottom of the heat preservation cylinder assembly is supported on the furnace bottom curing felt and arranged between t