Patent ID: 8747551

Claim:
A producing method of a silicon monocrystal, comprising: adding phosphorus (P) and germanium (Ge) into a silicon melt or adding phosphorus into a silicon/germanium melt; and growing a silicon monocrystal from the silicon melt by a Czochralski method; wherein: a phosphorus concentration [P] L (atoms/cm 3 ) in the silicon melt, a Ge concentration [Ge](atoms/cm 3 ) in the silicon monocrystal, an average temperature gradient G ave (K/mm) and a pull speed V (mm/min) are controlled to satisfy a formula (1) as follows; and a phosphorus concentration [P](atoms/cm 3 ) and the Ge concentration [Ge](atoms/cm3) in the silicon monocrystal satisfy a relationship according to a formula (2) as follows while growing the silicon monocrystal, where d Si (Å) represents a lattice constant of silicon, r Si (Å) represents a covalent radius of silicon, r P (Å) represents a covalent radius of phosphorus, and r Ge (Å) represents a covalent radius of Ge: [ P ] L + ( 0.3151 × [ Ge ] + 3.806 × 10 18 ) / 1.5 < 0.5 × ( G ave / V + 43 ) × 10 19 ( 1 ) ( ( r Ge - r Si r Si ) × [ Ge ] [ Si ] + ( r p - r Si r Si ) × [ P ] [ Si ] ) × d Si < - 4.24736 × 10 - 23 × [ P ] + 2.78516 × 10 - 3 . ( 2 )