Systems and methods are described for controlled crack propagation in a material using ultrasonic waves. A first stress in applied to the material such that the first stress is below a critical point of the material and is insufficient to initiate cracking of the material. A controlled ultrasound wave is then applied to the material causing the total stress applied at a crack tip in the material to exceed the critical point. In some implementations, the controlled cracking is used for wafering of a material.

A silicon wafer forming method includes: a block ingot forming step of cutting a silicon ingot to form block ingots; a planarizing step of grinding an end face of the block ingot to planarize the end face; a separation layer forming step of applying a laser beam of such a wavelength as to be transmitted through silicon to the block ingot, with a focal point of the laser beam positioned in the inside of the block ingot at a depth from the end face of the block ingot corresponding to the thickness of the wafer to be formed, to form a separation layer; and a wafer forming step of separating the silicon wafer to be formed from the separation layer.

Provided is a cutting method of cutting a workpiece by using a cutting apparatus including a chuck table configured to hold the workpiece and a cutting unit having a cutting blade configured to cut the workpiece held by the chuck table and an ultrasonic vibrator configured to ultrasonically vibrate the cutting blade in a radial direction of the cutting blade. The cutting method includes a holding step of holding the workpiece by the chuck table, and a cutting step of performing ultrasonic cutting that cuts the workpiece by the cutting blade vibrated ultrasonically and normal cutting that cuts the workpiece by the cutting blade not vibrated ultrasonically on the same cutting line of a plurality of cutting lines set on the workpiece.

An acoustic cleaving system are described for initiating and controlling crack propagation. In an embodiment, the system includes an acoustic generator that includes a piezoelectric device; a high-voltage power supply; and an acoustic cleaving circuit. The acoustic cleaving circuit includes a push-pull circuit coupled to the piezoelectric device and coupled to the high-voltage power supply, and a capacitor bank that includes one or more capacitors coupled in parallel to the push-pull circuit. In one embodiment, the push-pull circuit is for receiving at least one input signal and for producing an amplified output signal to drive the piezoelectric device.

After ultrasonic waves have been applied via a layer of liquid to an ingot for separating the ingot along separation layers formed therein to thereby produce a wafer from the ingot, the wafer and the ingot are moved relatively to each other along a direction in which the separation layers extend, thereby pulling apart the wafer and the ingot from each other.

To provide a method of processing a tempered glass in which a length of time required for manufacturing one plate of a product glass is significantly reduced while the quality of the product glass is secured. In the method of processing the tempered glass in which a stacked block (1a) acting as a chemical tempered glass (1) is processed by using a processing device (8) under a condition that the processing device (8) is rotated and vibrated, the stacked block (1a) is cut out from a stack (1A) acting as the chemical tempered glass (1) by using a dicing blade (84), prior to the processing of the stacked block (1a) by using the processing device (8), and a finishing to an outer periphery of the stacked block (1a) is also performed during the processing of the stacked block (1a) by using the processing device (8).

A honeycomb catalyst body includes a tubular honeycomb base material having porous partition walls to define and form a plurality of cells extending as through channels of a fluid from one end surface from which the fluid flows in to the other end surface from which the fluid flows out, and a catalyst loaded onto the partition walls. In the honeycomb base material, at least one slit which is open in a side surface of the honeycomb base material is formed, and a width of the slit is from 1.0 to 10.0 mm.

An ultrasonic micron precision molding apparatus includes: an ultrasonic generating module, a tool and an amplitude transformer. The ultrasonic generating module provides ultrasonic frequency vibration. The tool is disposed below the ultrasonic generating module, and has a micron-level precision structure. The amplitude transformer is disposed between the ultrasonic generating module and the tool and has a first section and a second section, the first section is disposed at the junction of the amplitude transformer and the tool, and the distance between the second section and the tool is longer than the distance between the first section and the tool, wherein the width of the first section is greater than the width of the second section.

A semiconductor substrate manufacturing method includes: epitaxially growing a columnar III nitride semiconductor single crystal on a principal place of a circular substrate; removing a hollow cylindrical region at an outer peripheral edge side of the III nitride semiconductor single crystal to leave a solid columnar region at an inside of the hollow cylindrical region of the III nitride semiconductor single crystal; and slicing the solid columnar region after removing the hollow cylindrical region. The hollow cylindrical region is removed such that the shape of the III nitride semiconductor single crystal is always keeps an axial symmetry that a center axis of the III nitride semiconductor single crystal is defined as a symmetric axis.