Abstract: The present invention provides a fuel cell unit, fuel cell unit array, fuel cell module and fuel cell system that can achieve a reduction in size and costs.

Abstract: Disclosed is a method of fabrication of high quality silicon single crystal at high growth rate. The method grows silicon single crystal from silicon melt by Czochralski method, wherein the silicon single crystal is grown according to conditions that the silicon melt has an axial temperature gradient determined according to an equation, {(?Tmax??Tmin)/?Tmin}×100?10, wherein ?Tmax is a maximum axial temperature gradient of the silicon melt and ?Tmin is a minimum axial temperature gradient of the silicon melt, when the axial temperature gradient is measured along an axis parallel to a radial direction of the silicon single crystal.