A silicon single crystal is pulled up such that nitrogen concentration of the crystal is 110.sup.11 to 210.sup.13 atoms/cm.sup.3, the crystal cooling rate is about 4.2 C./min at a temperature of a silicon melting point to 1350 C. and is about 3.1 C./min at a temperature of 1200 C. to 1000 C., and oxygen concentration of a wafer is 9.510.sup.17 to 13.510.sup.17 atoms/cm.sup.3. After a heat treatment is performed on the wafer sliced from the silicon single crystal in a treatment condition of 875 C. for about 30 min, growth of an epitaxial layer is caused. Thus, an epitaxial wafer in which the number of epitaxial defects is not increased while maintaining predetermined oxygen concentration and slips do not occur is produced.

A silicon single crystal is pulled up such that nitrogen concentration of the crystal is 110.sup.11 to 210.sup.13 atoms/cm.sup.3, the crystal cooling rate is about 4.2 C./min at a temperature of a silicon melting point to 1350 C. and is about 3.1 C./min at a temperature of 1200 C. to 1000 C., and oxygen concentration of a wafer is 9.510.sup.17 to 13.510.sup.17 atoms/cm.sup.3. After a heat treatment is performed on the wafer sliced from the silicon single crystal in a treatment condition of 875 C. for about 30 min, growth of an epitaxial layer is caused. Thus, an epitaxial wafer in which the number of epitaxial defects is not increased while maintaining predetermined oxygen concentration and slips do not occur is produced.

Disclosed herein are a treatment apparatus and method for a waste steam generator, and an installation method of a treatment apparatus for a waste steam generator. The treatment apparatus includes a cutting part for cutting a body of a waste steam generator, a driving part for driving the cutting part, and a support frame for supporting the cutting part and the driving part, wherein the support frame is coupled to an outer peripheral surface of the body of the waste steam generator in a divided state, and the cutting part is driven and cuts the body in a state in which the support frame is coupled to the outer peripheral surface of the body. Consequently, since the treatment apparatus is easily moved and installed, an installation time of the treatment apparatus may be shortened and an exposure time of a worker can be reduced.

Embodiments herein provide an abrasive saw chain that includes drive links and tie straps coupled to one another. Cutting elements, such as diamond cutting elements, may be coupled to upper surfaces of respective drive links. An upper surface of the tie strap may contact a lower surface of a cutting element to provide support for the cutting element. The tie strap may include a limiting feature to contact front and/or back surfaces of adjacent cutting elements when the links traverse an elongate portion of a guide bar. Alternatively, or additionally, the drive links may include a mating surface that contacts a mating surface of an adjacent drive link when the drive links traverse the elongate portion of the guide bar. Other embodiments may be described and/or claimed.

Embodiments herein provide an abrasive saw chain that includes drive links and tie straps coupled to one another. Cutting elements, such as diamond cutting elements, may be coupled to upper surfaces of respective drive links. An upper surface of the tie strap may contact a lower surface of a cutting element to provide support for the cutting element. The tie strap may include a limiting feature to contact front and/or back surfaces of adjacent cutting elements when the links traverse an elongate portion of a guide bar. Alternatively, or additionally, the drive links may include a mating surface that contacts a mating surface of an adjacent drive link when the drive links traverse the elongate portion of the guide bar. Other embodiments may be described and/or claimed.

The present invention relates to an automatic machining device for a high-speed rail pantograph carbon contact strip and a machining method therefor. The automatic machining device is sequentially provided with a milling position, a sawing position and a chamfering position, and comprises a rack, a band sawing machine, a workpiece milling device, a workpiece chamfering device, a CNC computer numerical control system and a pneumatic system. A carbon contact strip workpiece to be machined is arranged on the rack and is sequentially subjected to milling, sawing and chamfering machining; and a saw frame of the band sawing machine is also provided with a saw band upper guide servo rotating device and a saw band lower guide servo rotating device, and the saw band upper guide servo rotating device and the saw band lower guide servo rotating device can freely, synchronously and correspondingly rotate a band saw blade within a certain range. In the present invention, a carbon contact strip is machined by means of a sawing mode, the processes of sawing, milling and chamfering are integrated on one device, and the processes of milling, sawing and chamfering can be automatically completed after once clamping, thereby saving materials, and increasing the working efficiency.

The present invention relates to an automatic machining device for a high-speed rail pantograph carbon contact strip and a machining method therefor. The automatic machining device is sequentially provided with a milling position, a sawing position and a chamfering position, and comprises a rack, a band sawing machine, a workpiece milling device, a workpiece chamfering device, a CNC computer numerical control system and a pneumatic system. A carbon contact strip workpiece to be machined is arranged on the rack and is sequentially subjected to milling, sawing and chamfering machining; and a saw frame of the band sawing machine is also provided with a saw band upper guide servo rotating device and a saw band lower guide servo rotating device, and the saw band upper guide servo rotating device and the saw band lower guide servo rotating device can freely, synchronously and correspondingly rotate a band saw blade within a certain range. In the present invention, a carbon contact strip is machined by means of a sawing mode, the processes of sawing, milling and chamfering are integrated on one device, and the processes of milling, sawing and chamfering can be automatically completed after once clamping, thereby saving materials, and increasing the working efficiency.

An amount of warp of a wafer is not only reduced, but the amount of warp of the wafer is also accurately controlled to a desired amount. The present invention relates to a method for slicing a semiconductor single crystal ingot, by which a cylindrical semiconductor single crystal ingot is bonded to and held by a holder in a state where the ingot is rotated at a predetermined rotation angle around a crystal axis of the ingot different from a center axis of a cylinder of this ingot and the ingot is sliced by a cutting apparatus in this state. The predetermined rotation angle at the time of bonding and holding the ingot with the use of the holder in such a manner that an amount of warp of a wafer sliced out by the cutting apparatus becomes a predetermined amount.

An amount of warp of a wafer is not only reduced, but the amount of warp of the wafer is also accurately controlled to a desired amount. The present invention relates to a method for slicing a semiconductor single crystal ingot, by which a cylindrical semiconductor single crystal ingot is bonded to and held by a holder in a state where the ingot is rotated at a predetermined rotation angle around a crystal axis of the ingot different from a center axis of a cylinder of this ingot and the ingot is sliced by a cutting apparatus in this state. The predetermined rotation angle at the time of bonding and holding the ingot with the use of the holder in such a manner that an amount of warp of a wafer sliced out by the cutting apparatus becomes a predetermined amount.

The present invention relates to a wall or floor chain sawing device (1), comprising a chain bar assembly (37) which in turn comprises a chain bar (2) having a longitudinal extension (17) and guiding a chain (3) at least partly around its perimeter. The chain bar assembly (37) further comprises a chain bar housing (6) that is attached to, and partially covers, the chain bar (2) and the chain (3). The chain sawing device (1) comprises a motor (9), a track interface (7) that is arranged to co-operate with a guiding track (8), and a power transmission arrangement (10) that is adapted to transfer a motion from said motor (9) to the chain (3). The sawing device (1) comprises a first pivotable support rod (12) and a second pivotable support rod (13), where each pivotable support rod (12, 13) has a corresponding first end (12a, 13a) and a second end (12b, 13b). Each first end (12a, 13a) is at least indirectly pivotably attached to the motor (9), and each second end (12b, 13b) is at least indirectly pivotably attached to the chain bar assembly (37).