Texas Instruments Corporation

Lawrence D Dyer

Jerry B Medders

John Britton Robbins

Timothy J Hogan

Vikki S Simpson

Keith M Easton

James A Kennon

Anderson D McGregor

Tom G Gullett

Frank Allen

Mike Brenner

Anthony E Stephens

Frederick O Meyer, Iii

Lisa A Lester

Sean Christopher O'Brien

Eugene C Davis

Michael A Mignardi

Robert G McKenna

Mohendra S Bawa

Laurinda W Ng

Jerry D Smith

Franklin L Allen

Michael R Head

Clyde A King

Joseph G Harden

Robert M Montgomery

Dempsey McGregor

Joel B Jones

Michael Cunningham

Ronald S Croff

Bobby R Robbins

Arthur R Clark

Danny R Newton

Douglas W Bilderback

A method of fabricating a monolithic device, preferably a micromechanical device, from a wafer (20) by carefully selecting the composition of two or more layers of photoresist (52,54). The present invention uses a superhard protective layer such as DLC or TiW deposited over the partially fabricated device prior to a partial-saw. This superhard protective layer reduces the generation of defects in the underlying photoresist layers, and allows a wet chemical HF acid to etch away particles and damage of the underlying oxide edges. A 6% BHF solution can be utilized. The present invention substantially improves the yield of micromechanical devices.

Method of reducing wafer particles after partial saw using a superhard

A method of fabricating a monolithic device, preferably a micromechanical device, from a wafer (20) by carefully selecting the composition of two or more layers of photoresist (52,54). The present invention comprises choosing compatible photoresist layers to avoid generating defects in the layers of photoresist which could allow a wet chemical HF acid etch process to damage an underlying micromechanical device. The present invention allows a very strong solution of hydrofluoric acid to be utilized to remove particles and debris after a partial-saw process, and to remove a damaged portion of an underlying CMOS layer (22) at a region (68) proximate a kerf (62). Using an HF solution having a concentration of about 6% is desired. The present invention substantially improves the yield of micromechanical devices.

Method of reducing wafer particles after partial saw

A method of separating wafers, such as those used for semiconductor device manufacture, into die. A partly fabricated wafer is covered with a protective coating over its top surface (10). The wafer is then inscribed to define separation lines between die, with the separation lines being of a predetermined depth (12). The protective coating is then removed (14), and at least one processing step is performed at the wafer level (15, 22-24), before the inscribed wafer is separated into die. Then, the wafer is separated into die along the separation lines (17).

Separation of wafer into die with wafer-level processing

An edge polishing system (20, 320) and method for edge polishing semiconductor wafers is disclosed. The system (20, 320) includes a loader (22, 326), a polisher (24, 328), an unloader (26, 330), and a controller (28, 335). The method includes the steps of loading wafers (28), and spacers (30) into a loader (22) to form a stack (36), moving the stack (36) into a polisher (24) and causing polisher (24) to polish the stack (36), then moving the stack (36) to an unloader (26), which semiautomatically removes the wafers (28) and spacers (30). The system (20) may include a controller (28) for entering the appropriate commands.

Semiconductor wafer edge polishing system and method

The protection to the backside of the semiconductor wafer is accomplished by applying a layer of silicon oxide or silicon nitride or other deposited material to the back surface of a semiconductor wafer to protect against particles, scratches, and etching by mild caustic solutions. The layer remains in place during all three processes, edge pre-polish, mirror edge polish, and wafer polish.

Method of surface protection of a semiconductor wafer during polishing

An apparatus and method of contouring the edge of a semiconductor wafer in a fiduciary mark notch utilizes a contouring wheel or burr having a smaller diameter than the diameter of the fiduciary mark notch.

Notch beveling on semiconductor wafer edges

A system and method for polishing the edges of a plurality of semiconductor wafers rotates a stack of wafers against a polish one or more pads such that both the wafer edges and the sides of the edges are polished to a mirror finish. The polish pad has a series of grooves through which the wafer edges are passed to polish the sides of the wafer edges, or two pads are used, one with grooves and one without grooves.

Method for polishing semiconductor wafer edges

An apparatus stacks semiconductor wafers and spacers and clamps them in an axial alignment for mounting in a semiconductor wafer edge polishing machine. After edge polishing, the apparatus separates the wafers and spacers and delivers them respectively into separate cassettes for further processing or recycling.

Semiconductor wafer stacking apparatus and method

A method for polishing the edges of a plurality of semiconductor wafers rotates a stack of wafers against a polish one or more pads such that both the wafer edges and the sides of the edges are polished to a mirror finish. The polish pad has a series of grooves through which the wafer edges are passed to polish the sides of the wafer edges, or two pads are used, one with grooves and one without grooves.

Trace quantities of elemental iodine are added to deionized water used in the manufacture of semiconductor materials and devices in order to sterilize the water and the delivery system of microscopic life forms, and to leave the iodine in the flow all the way through processing except for those process steps where iodine may be detrimental to the process step.

Iodine sterilization of deionized water in semiconductor processing

A system and method for controlling the tension of an internal diameter saw blade by controlling the temperature of the blade while it is still rotating. The blade temperature is controlled by regulating the temperature of the wash water flow associated therewith. In one embodiment blade tension is periodically measured and, when the tension falls below a predetermined limit, the temperature of the wash water stream is decreased for a period of time until the tension increases to a preselected value.

Control of internal diameter saw blade tension in situ

A system and method for reducing kerf loss and controlling the tension and lateral vibration of an internal diameter saw blade by controlling the temperature of the blade while it is still rotating. The blade temperature is controlled by regulating the temperature of the cutting fluid flow associated therewith. In one embodiment blade tension is periodically measured and, when the tension falls below a predetermined limit, the temperature of the cutting fluid stream is decreased for a period of time until the tension increases to a preselected value.

Kerf loss reduction in internal diameter sawing

A system for measuring the flexure of a saw blade in situ includes in one embodiment a non-contact displacement sensor and means for directing a fluid flow at the blade adjacent the sensor. The deflection of the blade by the fluid flow is detected by the sensor which generates a signal related to blade flexure. The system indicates when a saw blade is correctly tensioned or when retensioning is required.

Method for measuring saw blade flexure

The disclosure relates to the growth of semiconductor single crystals, i.e., either by the pedestal method or by the Czochralski method, free from dislocations, particularly in the difficult directions of growth, such as &lt;110&gt;. The method causes dislocations parallel to the growth axis to grow away from the axis under the influence of a changing crystal diameter. The thickness of the stem portion of the crystal is controlled so that it has first a long thin portion to get rid of dislocations on the {111} planes that are inclined to the &lt;110&gt; axis and then a portion in which the residual dislocations are permitted to terminate at the surface. The latter portion may be generated in several ways. One way is to follow the long narrow diameter portion with a section of substantially larger diameter followed by a further narrow diameter portion. This combination is repeated one or more times to insure freedom from dislocations in the resulting crystal. By having the alternate thin and thick regions, the dislocations are gradually moved away from the axis of the crystal and toward the periphery where they will have a greater probability of terminating on a surface, thereby removing the dislocations.

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Richardson, TX, United States of America

Lawrence D Dyer