A method of evaluating metal contamination by measuring the amount of metal contaminants to a silicon wafer in a rapid thermal processing apparatus includes steps of obtaining a Si single crystal grown by the Czochralski method at a pulling rate of 1.0 mm/min or lower, the crystal having oxygen concentration of 1.310.sup.18 atoms/cm.sup.3 or less, slicing silicon wafers from the Si single crystal except regions of 40 mm toward the central portion from the head of the single crystal and 40 mm toward the central portion from the tail, heat-treating the silicon wafer with a rapid thermal processing apparatus and transferring contaminants from members in a furnace of the rapid thermal processing apparatus to the silicon wafer, and measuring a lifetime of the silicon wafer to which contaminants are transferred.

A method for growing a single crystal silicon ingot by the continuous Czochralski method is disclosed. The melt depth and thermal conditions are constant during growth because the silicon melt is continuously replenished as it is consumed, and the crucible location is fixed. The critical v/G is determined by the hot zone configuration, and the continuous replenishment of silicon to the melt during growth enables growth of the ingot at a constant pull rate consistent with the critical v/G during growth of a substantial portion of the main body of the ingot. The continuous replenishment of silicon is accompanied by periodic or continuous nitrogen addition to the melt to result in a nitrogen doped ingot.

A method for growing a single crystal silicon ingot by the continuous Czochralski method is disclosed. The melt depth and thermal conditions are constant during growth because the silicon melt is continuously replenished as it is consumed, and the crucible location is fixed. The critical v/G is determined by the hot zone configuration, and the continuous replenishment of silicon to the melt during growth enables growth of the ingot at a constant pull rate consistent with the critical v/G during growth of a substantial portion of the main body of the ingot. The continuous replenishment of silicon is accompanied by periodic or continuous nitrogen addition to the melt to result in a nitrogen doped ingot.

Single crystal semiconductor ingots are pulled from a melt contained in a crucible by a method of controlling the pulling the single crystal in a phase in which an initial cone of the single crystal is grown until a phase in which the pulling of a cylindrical section of the single crystal is begun, by measuring the diameter Dcr of the initial cone of the single crystal and calculating the change in the diameter dDcr/dt; pulling the initial cone of the single crystal from the melt at a pulling rate vp(t) from a point in time t1 until a point in time t2, starting from which the pulling of the cylindrical section of the single crystal in conjunction with a target diameter Dcrs is begun, wherein the profile of the pulling rate vp(t) from the point in time t1 until the point in time t2 during the pulling of the initial cone is predetermined by means of an iterative computation process.

A method of manufacturing an epitaxial silicon wafer that includes growing a silicon single crystal ingot doped with a boron concentration of 2.710.sup.17 atoms/cm.sup.3 or more and 1.310.sup.19 atoms/cm.sup.3 or less by the CZ method; producing a silicon substrate by processing the silicon single crystal ingot; and forming an epitaxial layer on a surface of the silicon substrate. During growing of the silicon single crystal ingot, the pull-up conditions of the silicon single crystal ingot are controlled so that the boron concentration Y (atoms/cm.sup.3) and an initial oxygen concentration X (10.sup.17 atoms/cm.sup.3) satisfy the expression X4.310.sup.19Y+16.3.

A semiconductor wafer comprising single-crystal silicon has defined concentrations of oxygen, nitrogen and hydrogen; the semiconductor wafer further contains BMD seeds having a density averaged over the radius of not less than 110.sup.5 cm.sup.3 and not more than 110.sup.7 cm.sup.3; surface defects having a density averaged over the radius of not less than 1100 cm.sup.2; and BMDs, whose density is not lower than a lower limit of 510.sup.8/cm.sup.3. The semiconductor wafers are produced by a process which enables obtention of the required ranges of concentrations of oxygen, nitrogen, hydrogen, BMD seeds, and BMD's.

Single crystal semiconductor wafers comprise oxygen and an n-type dopant, and are produced by a process comprising providing a silicon melt containing n-type dopant in a quartz crucible, the melt having an initial height hM; heating the melt from the side by selectively supplying heat to an upper volume of the melt having an initial height hm, wherein hm is smaller than hM; pulling a single crystal of silicon from the melt by the CZ method with a pulling velocity V; heating the melt from above in the region of a phase boundary between the growing single crystal and the melt; heating the melt from above in the region of a surface of the melt; subjecting the melt to a magnetic field; counterdoping the melt with p-type dopant; and
separating the semiconductor wafer of single-crystal silicon from the single crystal. An apparatus for accomplishing the process is also disclosed.

A method for growing a single crystal silicon ingot by the Czochralski method having reduced deviation in diameter is disclosed.

A method of fabricating a turbine engine part, the method including fabricating an ingot out of ceramic material of eutectic composition by performing the Czochralski process including putting a seed of the ingot that is to be obtained into contact with a molten bath of a mixture of eutectic composition in order to initiate the formation of the ingot on the seed, the mixture including at least two ceramic compounds; drawing the ingot from the molten bath while imposing on the ingot that is being formed a drawing speed less than or equal to 10 mm/h together with rotation at a speed of rotation less than or equal to 50 rpm; and machining the ingot as fabricated in this way in order to obtain the turbine engine part.

Single crystal silicon with <100> orientation is doped with n-type dopant and comprises a starting cone, a cylindrical portion and an end cone, a crystal angle being not less than 20 and not greater than 30 in a middle portion of the starting cone, the length of which is not less than 50% of a length of the starting cone, and edge facets extending from a periphery of the single crystal into the single crystal, the edge facets in the starting cone and in the cylindrical portion of the single crystal in each case having a length which is not more than 700 m.