NOVELTY - The method for producing an ingot made of upgraded metallurgical-grade silicon for penetration-resistant p-type solar cells (1) is claimed, where the ingot has a height originating from a bottom with p-type silicon to a head with n-type silicon and a basic conductivity is adjusted to a value of 1.0-1.25 Omega cm with a relative height of 5% over the ingot bottom and at the ingot bottom by doping the upgraded metallurgical-grade silicon. The increase of the basic conductivity over a determined value is prevented between the bottom and the head of the ingot by partial secondary doping.    USE - Method for producing an ingot made of upgraded metallurgical-grade silicon for penetration-resistant p-type solar cells.    ADVANTAGE - The method ensures economical production of the ingot with high efficiency.    DETAILED DESCRIPTION - The method for producing an ingot made of upgraded metallurgical-grade silicon for penetration-resistant p-type solar cells (1) is claimed, where the ingot has a height originating from a bottom with p-type silicon to a head with n-type silicon and a basic conductivity is adjusted to a value of 1.0-1.25 Omega cm with a relative height of 5% over the ingot bottom and at the ingot bottom by doping the upgraded metallurgical-grade silicon. The increase of the basic conductivity over a determined value is prevented between the bottom and the head of the ingot by partial secondary doping, where the determined value is 2.5 Omega cm. The partial secondary doping is carried out, so that the basic conductivity of the p-type silicon does not drop below 1 Omega cm. The silicon is solidified in a crystallization furnace in a molten and aligned manner. The silicon concentration of greater than or equal to 0.2 ppma contains phosphorus and silicon concentration of greater than or equal to 0.05 ppma contains boron and impurities of iron and/or calcium. For the doping and/or secondary doping, boron, gallium, aluminum, zinc, indium, nitrogen, phosphorus, arsenic and/or antimony is used. An overcompensation of the original dopant contained in the silicon takes place by doping and/or secondary doping. INDEPENDENT CLAIMS are included for:    (1) an ingot made of upgraded metallurgical-grade silicon for penetration-resistant p-type solar cells; and    (2) a method for producing a penetration-resistant p-type solar cell made of upgraded metallurgical-grade silicon.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic representation of a solar cell.    Solar cell (1)    Silicon wafer (2)    Emitter (3)    Antireflection layer (4)    Front contact (5)    Rear contact. (6)