Patent classifications
B28D5/0052
PHOTOVOLTAIC STRUCTURE CLEAVING SYSTEM
A cleaving system and method are described. The system can include a holding apparatus to retain a photovoltaic structure at a center section of a cleaving platform. The system can further include a contact apparatus to make contact with the photovoltaic structure and separate it into a plurality of strips. During operation, the system can activate an actuator to move the contact apparatus against the photovoltaic structure, thereby separating the photovoltaic structure into strips.
Photovoltaic structure cleaving system
A cleaving system is described. The system can include a holding apparatus to retain a photovoltaic structure at a center section of a cleaving platform. The system can further include a contact apparatus to make contact with the photovoltaic structure and separate it into a plurality of strips. During operation, the system can activate an actuator to move the contact apparatus against the photovoltaic structure, thereby separating the photovoltaic structure into strips.
RAPID WAFERING OF WIDE BANDGAP SUBSTRATES
This invention concerns cleaving of silicon carbide (SiC) wafers from boule to reduce the cost of manufacturing SiC substrates. We use Vickers diamond tips to initiate a crack, similar to a hardness tester, and a chisel type wedge to drive the crack at a depth of 500 micron. We use the same machine to initiate and propagate the crack. We do not use either a wire saw or a laser or ion implantation to transfer a layer. We prevent the crack from deviating from its plane and we reduce the consumption of diamond and extend the lifetime of Vickers indenters while machining SiC under high load. The rate of diamond consumption is on par or even less than the multi-wire saw. We use parallel indentation in conjunction with fast motors and actuators to speed up the cleavage process and increase the throughput which makes it competitive with the multi-wire saw.
Peeling apparatus
There is provided a peeling apparatus including an ingot holding unit that has a holding surface for holding an ingot, a wafer holding unit that is capable of approaching and separating from the ingot holding unit and has a holding surface for holding under suction a wafer to be produced, and a cleaning brush that cleans peel-off surfaces at which the wafer to be produced has been peeled off from the ingot and thereby removes peeling swarf.
Peeling method and peeling apparatus
An ultrasonic wave is applied to an upper surface of an ingot via a liquid layer, in a state in which an outer circumferential region of a lower surface of the ingot is sucked. A lower side around an outer circumferential arc-shaped portion of the lower surface of the ingot is open so that liquid that serves as a medium of the ultrasonic wave does not collect around the outer circumferential arc-shaped portion of the lower surface of the ingot. As a result, a peel-off layer formed in the ingot is not immersed in liquid when an ultrasonic wave is applied to the upper surface of the ingot via the liquid layer. Consequently, even when the ingot becomes thin, the ingot can be separated at the peel-off layer, and a wafer can be peeled off from the ingot.
MANUFACTURING METHOD OF WAFER
There is provided a manufacturing method of a wafer for manufacturing from a workpiece the wafer having a thickness smaller than the distance between a first surface and a second surface of the workpiece. The workpiece is an ingot of GaN or a single-crystal substrate of GaN. The method includes forming a separation layer in the workpiece by relatively moving, along a predetermined direction, the workpiece and the focal point of a pulsed laser beam transmitting through the workpiece in a state in which the first surface is irradiated with the laser beam and the focal point is positioned at a predetermined depth position in the workpiece, and separating the wafer from the workpiece by using the separation layer as the point of origin. The angle between a crystal orientation represented by <10
Method of manufacturing semiconductor wafers
A manufacturing method of semiconductor wafers includes preparing a ingot having a first major surface and a second major surface in a back side of the first major surface, a peeling layer being formed in the ingot along the first major surface; and applying a load to the ingot from outside thereof with respect to a surface direction along the first major surface such that a moment with a supporting point which is a first end of the ingot in the surface direction acts on the ingot, thereby peeling a wafer precursor from the ingot. Also, a dynamic force may be applied to the ingot such that a tensile stress along an ingot thickness direction acts on an entire area of the ingot in the surface direction, thereby peeling the wafer precursor from the ingot.
Method for cutting substrate elements
In a method, substrate elements are provided wherein each substrate element has a first side and a second side meeting at a corner point. The substrate elements are picked and then placed on a support device in alignment. A cutting operation is then performed where each of the substrates elements are cut along a cut line having a common first direction which intersects the first and second sides of each of the substrate elements in order to create a third side on each substrate element. The third side of each of the substrate elements meets the first and the second sides at corresponding corner points.
Dividing apparatus
A dividing apparatus is provided with a second camera that forms a second image to be used for determining whether or not a wafer is divided at a first projected dicing line. That is, in the dividing apparatus, whether or not the wafer is divided at the first projected dicing line can be checked in reference to the second image. Hence, in the dividing apparatus, even in a case where part of the wafer remains at the first projected dicing line and the wafer is not divided, a dividing unit can be operated again to divide the wafer at the first projected dicing line. Consequently, in the dividing apparatus, the wafer can reliably be divided at the first projected dicing line.
Dividing method of workpiece
A tape is stuck to the front surface of a workpiece in such a manner that the direction in which the stretch rate becomes the lowest when a predetermined force is applied to the tape is non-parallel to each of multiple planned dividing lines extending in a lattice manner. In this case, each of the multiple planned dividing lines does not extend along the direction perpendicular to this direction. This can reduce the ratio of the region to which the tape does not stick in the front surface of the workpiece in the vicinity of the boundary between each of the multiple planned dividing lines and a region in which a device is formed and suppress deterioration of the processing quality when the workpiece is divided from the back surface side by a cutting blade.