Tencor Instruments

Kla Tencor Corporation

Varian Associates, Inc.

Kla-tencor Technologies Corporation

William R Wheeler

George J Kren

Steven G Eaton

Amin Samsavar

Rusmin Kudinar

Karel Urbanek

Steven W Meeks

Hung Phi Nguyen

Peter G Panagas

Thomas Harding McWaid

David D Clementson

Jian-Ping Zhuang

Ronny Soetarman

Vamsi Mohan Velidandla

Anoop K Somanchi

Steven R Lee

In one embodiment, a system to measure defects on a surface of a wafer and an edge of the wafer using a single tool comprises a radial motor to move an optical head in a radial direction to detect defects at locations displaced from the edge of the wafer, and a rotational motor to rotate the optical head around the edge of the wafer to detect defects on the edge of the wafer.

Wafer edge inspection

A profiler or scanning probe microscope may be scanned across a sample surface with a distance between them controlled to allow the sensing tip to contact the surface intermittently in order to find and measure features of interest. The distance is controlled so that when the sensing tip is raised or lowered to touch the sample surface, there is no lateral relative motion between the tip and the sample. This prevents tip damage. Prior knowledge of the height distribution of the sample surface may be provided or measured and used for positioning the sensing tip initially or in controlling the separation to avoid lateral contact between the tip and the sample. The process may also be performed in two parts: a fast find mode to find the features and a subsequent measurement mode to measure the features. A quick step mode may also be performed by choosing steps of lateral relative motion to be smaller than 100 nanometers to reduce probability of tip damage. In this mode, after each vertical step to increase the separation between the tip and the sample, it is detected as to whether the tip and the sample are in contact. If they are still in contact after the vertical step, one or more vertical steps are taken to increase the separation, and no vertical step to reduce the separation is taken and no lateral relative motion is caused until it is determined that the tip and the sample are no longer in contact.

System for sensing a sample

In one embodiment, a system to inspect the edge of a wafer, comprises an surface analyzer assembly, a first drive assembly to impart linear motion between the surface analyzer and a first surface of the wafer, and a second drive assembly to impart rotary motion between the surface analyzer and the wafer about an axis parallel to the first surface of the wafer.

In one embodiment, a surface analyzer system comprises a radiation targeting assembly to target a radiation beam onto a surface; and a reflected radiation collecting assembly that collects radiation reflected from the surface, wherein the reflected radiation collecting assembly comprises a mirror to collect radiation reflected from the surface.

A dual stage scanning instrument includes a sensor for sensing a parameter of a sample and coarse and fine stages for causing relative motion between the sensor and the sample. The coarse stage has a resolution of about 1 micrometer and the fine stage has a resolution of 1 nanometer or better. The sensor is used to sense the parameter when both stages cause relative motion between the sensor assembly and the sample. The sensor may be used to sense height variations of the sample surface as well as thermal variations, electrostatic, magnetic, light reflectivity or light transmission parameters at the same time when height variation is sensed. By performing along scan at a coarser resolution and short scans a high resolution using the same probe tip or two probe tips at fixed relative positions, data obtained from the long and short scans can be correlated accurately.

Dual stage instrument for scanning a specimen

A dual stage scanning instrument includes a sensor for sensing a parameter of a sample and coarse and fine stages for causing relative motion between the sensor and the sample. The coarse stage has a resolution of about 1 micrometer and the fine stage has a resolution of 1 nanometer or better. The sensor is used to sense the parameter when both stages cause relative motion between the sensor assembly and the sample, The sensor may be used to sense height variations of the sample surface as well as thermal variations electrostatic, magnetic, light reflectivity or light transmission parameters at the same time when height variation is sensed. By performing along scan at a coarser resolution and short scans a high resolution using the same probe tip or two probe tips at fixed relative positions, data obtained from the long and short scans can be correlated accurately.

A profilometer has a constant force mechanism for biasing of the stylus arm. The mechanism has a centrally-aligned configuration of the moving magnet relative to the magnetic coil and also has a magnetic shield isolating these elements from other ferromagnetic materials in the assembly. The moving magnet is made of a material that is hard magnetically and the magnetic shield is made of a series of low hysteresis, high permeability materials. The force thus generated by the stylus biasing device is very linear with the drive current upon the magnetic coil at any particular position of the stylus, thereby allowing for control and predictability of the stylus force upon the surface to be profiled. This predictability is used for dynamic stylus force adjustments during profiling of a specimen. The profilometer is also equipped with a balanced, spring-loaded stylus-stabilizing sensor assembly, task-specific dual-view optics for protection of the delicate stylus assembly, and a temperature drift compensator.

Constant-force profilometer with stylus-stabilizing sensor assembly,

A stylus profilometer having a counterbalanced stylus with a motion transducer using a vane moving between parallel, spaced-apart, conductive plates which damp the motion of the vane by means of trapped air. The vane forms an electrode with the plates so that the combination is a pair of capacitors in a balanced bridge arrangement. Motion of the stylus causes an unbalance of the bridge indicative of the extent of stylus motion. A lever arm associated with the stylus has a tip influenced by a magnetic field which biases the stylus or controls force on a surface to be measured. The entire assembly has a very low moment of inertia to reduce the effects of vibration on the stylus and thereby increase resolution of the device and reduce damage to the substrate.

Profilometer stylus assembly insensitive to vibration

A first thermally conductive plate holds an article and heats the article with heating elements in the plate. Parallel rails support the first plate above a base. Cooling passageways for coolant flow are in a second thermally conductive plate. The second plate is supported spaced from the base by a shaft in a chamber of the second plate and a spring. During the heating phase, the second plate is spaced apart from the first plate. During the cooling phase, the second plate is urged by the spring into contact with the first plate, so that the second plate acts as a heat sink for the first plate. Vacuum suction and an annular elastomer seal around the top rim of the second plate clamp the first and second plates together in thermal communication. Vacuum suction in the chamber retracts the second plate from the first plate.

Apparatus for heating and cooling articles

A wafer handler featuring a carriage movable along a rail path, the carriage supporting an upright rotatable arm with a cantilevered wafer chuck. Elevators for raising and lowering trays containing wafer stacks are disposed on either side of the rail path. Each elevator has a curved track section which may be interposed along the rail path. The upright arm has a track follower, parallel to a boom supporting the wafer chuck and freely movable along the rail path, except when it encounters a curved track section. In this instance, the track follower will follow the curved track section, causing rotation of the arm, boom and wafer chuck, bringing the chuck into the wafer stack at an elevation determined by the elevator. In this manner, motion in the X, Y and Z planes may be provided for stacked wafers over extended distances.

Wafer handling apparatus

A wafer chuck and a wafer loading and unloading system wherein a flat support surface of the chuck has a plurality of peaks and valleys, with the peaks minimizing contact with the wafer, yet having sufficient contact area for wafer support without deformation. The peaks are provided with a top edge serving to dislodge particles from a wafer surface when loading the wafer onto the chuck. The loading system includes wafer pushing members for bringing a wafer to a desired position on the support surface.

Wafer chuck with wafer cleaning feature

A surface profile measuring instrument, which has a stylus supported on a linear elongated beam for linear scanning. The beam is supported by a mounting mechanism which compensates for tilt by means of a servo. The stylus is pushed and pulled along the beam for linear scans of desired length.

Growing community of inventors

Saratoga, CA, United States of America

William R Wheeler