Abstract: Methods for controlling the surface profiles of wafers sliced from an ingot with a wire saw include measuring an amount of displacement of a sidewall of a frame of the wire saw. The sidewall is connected to a bearing of a wire guide supporting a wire web in the wire saw. The measured amount of displacement of the sidewall is stored as displacement data. Based on the stored data, a pressure profile for adjusting a position of the sidewall is determined by a computing device. Pressure is applied to the sidewall using a displacement device according to the determined pressure profile to control the position of the sidewall.

Abstract: Crystal pulling systems for growing monocrystalline ingots from a melt of semiconductor or solar-grade material are described. The crystal pulling systems include seed chuck assemblies designed to reduce formation of deposits on components of the crystal pulling systems by reducing and inhibiting the formation of gas flow recirculation cells within the crystal pulling systems.

Abstract: In one aspect, a method of predicting warp in a plurality of wafers after an epitaxial layer deposition process is provided. The method includes receiving, by a processor, a measured resistivity of a first wafer of the plurality of wafers, receiving, by the processor, a measured shape of the first wafer after at least one of a grinding process and an etching process, and calculating, using the processor, a change in wafer shape during the epitaxial layer deposition process. The method further includes superposing, using the processor, the calculated shape change onto the measured shape of the first wafer to determine a post-epitaxial wafer shape and calculating, using the processor, a post-epitaxial warp value based on the determined post-epitaxial wafer shape.

Abstract: In one aspect, a method of predicting warp in a plurality of wafers after an epitaxial layer deposition process is provided. The method includes receiving, by a processor, a measured resistivity of a first wafer of the plurality of wafers, receiving, by the processor, a measured shape of the first wafer after at least one of a grinding process and an etching process, and calculating, using the processor, a change in wafer shape during the epitaxial layer deposition process. The method further includes superposing, using the processor, the calculated shape change onto the measured shape of the first wafer to determine a post-epitaxial wafer shape and calculating, using the processor, a post-epitaxial warp value based on the determined post-epitaxial wafer shape.

Abstract: A method of polishing a wafer is disclosed that includes determining a removal profile. The wafer is measured to determine a starting wafer profile and then the wafer is polished. The wafer is again measured after being polished to determine a polished wafer profile. The starting wafer profile and the polished wafer profile are compared to each other to determine the removal profile by computing the amount and shape of material removed from the first wafer during polishing.

Abstract: A platen for polishing a surface of a wafer has a reaction plate, a polishing plate, and a bladder. The reaction plate has a top and bottom surface, and defines a longitudinal axis. The polishing plate is positioned coaxially with the reaction plate. The polishing plate has a second top surface and a second bottom surface. The second top surface is adjacent to the bottom surface of the reaction plate. The bladder is coaxially located along a radially outer portion of either the top or bottom surface of the reaction plate. The bladder is connected with the polishing plate and able to expand to deform the polishing plate with respect to the bottom surface of the reaction plate.

Abstract: Methods are disclosed for determining mounting locations of ingots on a wire saw machine. The methods include measuring a test surface of a test wafer previously sliced by the wire saw machine from a test ingot to calibrate the system. A magnitude and a direction of an irregularity of the measured test surface of the test wafer is then determined. The mounting location is then determined for another ingot to be mounted on the ingot holder based on at least one of the magnitude and direction of the irregularity of the measured test surface of the test wafer.

Abstract: A method of polishing a wafer is disclosed that includes determining a removal profile. The wafer is measured to determine a starting wafer profile and then the wafer is polished. The wafer is again measured after being polished to determine a polished wafer profile. The starting wafer profile and the polished wafer profile are compared to each other to determine the removal profile by computing the amount and shape of material removed from the first wafer during polishing.

Abstract: A platen for polishing a surface of a wafer has a reaction plate, a polishing plate, and a bladder. The reaction plate has a top and bottom surface, and defines a longitudinal axis. The polishing plate is positioned coaxially with the reaction plate. The polishing plate has a second top surface and a second bottom surface. The second top surface is adjacent to the bottom surface of the reaction plate. The bladder is coaxially located along a radially outer portion of either the top or bottom surface of the reaction plate. The bladder is connected with the polishing plate and able to expand to deform the polishing plate with respect to the bottom surface of the reaction plate.

Abstract: Systems and methods are disclosed for modulating the hydrostatic pressure in a double side wafer grinder having a pair of grinding wheels. The systems and methods use a processor to measure the amount of electrical current drawn by the grinding wheels. Pattern detection software is used to predict a grinding stage based on the measured electrical current. The hydrostatic pressure is changed by flow control valves at each stage to change the clamping pressure applied to the wafer and to thereby improve nanotopology in the processed wafer.

Abstract: Methods are disclosed for controlling the displacement of bearings in a wire saw machine. The systems and methods described herein are generally operable to alter the nanotopology of wafers sliced from an ingot by controlling the shape of the wafers. The shape of the wafers is altered by controlling displacement of bearings in the wire saw by changing the temperature and/or flow rate of a temperature-controlling fluid circulated in fluid communication with bearings supporting wire guides of the saw. Different feedback systems can be used to determine the temperature of the fluid necessary to generate wafers having the desired shape and/or nanotopology.

Abstract: Systems and are disclosed for controlling the temperature of bearings in a wire saw machine. The systems described herein are generally operable to alter the nanotopology of wafers sliced from an ingot by controlling the shape of the wafers. The shape of the wafers is altered by controlling the temperature of bearings in the wire saw by changing the temperature and/or flow rate of a temperature-controlling fluid circulated in fluid communication with bearings supporting wire guides of the saw. Different feedback systems can be used to determine the temperature of the fluid necessary to generate wafers having the desired shape and/or nanotopology.

Abstract: Systems are disclosed for controlling the surface profiles of wafers cut in a wire saw machine. The systems and methods described herein are generally operable to alter the nanotopology of wafers sliced from an ingot by controlling the shape of the wafers. The shape of the wafers is altered by changing the temperature and/or flow rate of a temperature-controlling fluid circulated in fluid communication with bearings supporting wire guides of the saw. Different feedback systems can be used to determine the temperature of the fluid necessary to generate wafers having the desired shape and/or nanotopology.

Abstract: Methods are disclosed for controlling surface profiles of wafers cut in a wire saw machine. The systems and methods described herein are generally operable to alter the nanotopology of wafers sliced from an ingot by controlling the shape of the wafers. The shape of the wafers is altered by changing the temperature and/or flow rate of a temperature-controlling fluid circulated in fluid communication with bearings supporting wire guides of the saw. Different feedback systems can be used to determine the temperature of the fluid necessary to generate wafers having the desired shape and/or nanotopology.

Abstract: Processing a wafer using a double side grinder having a pair of grinding wheels. Warp data is obtained by a warp measurement device for measuring warp of a wafer as ground by the double side grinder. The warp data is received and a nanotopography of the wafer is predicted based on the received warp data. A grinding parameter is determined based on the predicted nanotopography of the wafer. Operation of the double side grinder is adjusted based on the determined grinding parameter.

Abstract: Systems and methods are disclosed for modulating the hydrostatic pressure in a double side wafer grinder having a pair of grinding wheels. The systems and methods use a processor to measure the amount of electrical current drawn by the grinding wheels. Pattern detection software is used to predict a grinding stage based on the measured electrical current. The hydrostatic pressure is changed by flow control valves at each stage to change the clamping pressure applied to the wafer and to thereby improve nanotopology in the processed wafer.

Abstract: Processing a wafer using a double side grinder having a pair of grinding wheels. Warp data is obtained by a warp measurement device for measuring warp of a wafer as ground by the double side grinder. The warp data is received and a nanotopography of the wafer is predicted based on the received warp data. A grinding parameter is determined based on the predicted nanotopography of the wafer. Operation of the double side grinder is adjusted based on the determined grinding parameter.

Abstract: Processing a wafer using a double side grinder having a pair of grinding wheels. Warp data is obtained by a warp measurement device for measuring warp of a wafer as ground by the double side grinder. The warp data is received and a nanotopography of the wafer is predicted based on the received warp data. A grinding parameter is determined based on the predicted nanotopography of the wafer. Operation of the double side grinder is adjusted based on the determined grinding parameter.

Abstract: A double side grinder comprises a pair of grinding wheels and a pair of hydrostatic pads operable to hold a flat workpiece (e.g., semiconductor wafer) so that part of the workpiece is positioned between the grinding wheels and part of the workpiece is positioned between the hydrostatic pads. At least one sensor measures a distance between the workpiece and the respective sensor for assessing nanotopology of the workpiece. In a method of the invention, a distance to the workpiece is measured during grinding and used to assess nanotopology of the workpiece. For instance, a finite element structural analysis of the workpiece can be performed using sensor data to derive at least one boundary condition. The nanotopology assessment can begin before the workpiece is removed from the grinder, providing rapid nanotopology feedback. A spatial filter can be used to predict the likely nanotopology of the workpiece after further processing.

Abstract: Processing a wafer using a double side grinder having a pair of grinding wheels. Warp data is obtained by a warp measurement device for measuring warp of a wafer as ground by the double side grinder. The warp data is received and a nanotopography of the wafer is predicted based on the received warp data. A grinding parameter is determined based on the predicted nanotopography of the wafer. Operation of the double side grinder is adjusted based on the determined grinding parameter.