Abstract: A semiconductor wafer metrology technique which corrects for the effect of electrostatic forces on an atmospheric buoyancy compensated weight force measurement of a semiconductor wafer. In one aspect a wafer is weighed in a faraday cage whose is measured independently. A change in the measured weight of the faraday cage can be used to correct the measure weight the wafer. In another aspect a direct electrostatic measurement can be converted into a weight correction using a predetermined correlation between an electrostatic charge measured by the charge meter and a weight error force. In another aspect the electrostatic measurement may be indirect, e.g. derived from varying the distance between the wafer and a grounded plate parallel to the wafer to effect a change in an electrostatic force between the grounded plate and the wafer.

Abstract: A semiconductor wafer fabrication metrology method in which process steps are characterised by a change in wafer mass, whereby during fabrication mass is used as a measurable parameter to implement statistical process control on the one or more of process steps. In one aspect, the shape of a measured mass distribution is compared with the shape of a predetermined characteristic mass distribution to monitor the process. An determined empirical relationship between a control variable of the process and the characteristic mass change may enable differences between the measured mass distribution and characteristic mass distribution to provide information about the control variable. In another aspect, the relative position of an individual measured wafer mass change in a current distribution provides information about individual wafer problems independently from general process problems.

Abstract: A semiconductor wafer fabrication metrology method in which process steps are characterised by a change in wafer mass, whereby during fabrication mass is used as a measurable parameter to implement statistical process control on the one or more of process steps. In one aspect, the shape of a measured mass distribution is compared with the shape of a predetermined characteristic mass distribution to monitor the process. An determined empirical relationship between a control variable of the process and the characteristic mass change may enable differences between the measured mass distribution and characteristic mass distribution to provide information about the control variable. In another aspect, the relative position of an individual measured wafer mass change in a current distribution provides information about individual wafer problems independently from general process problems.

Abstract: A semiconductor wafer fabrication metrology method in which process steps are characterized by a change in wafer mass, whereby during fabrication mass is used as a measurable parameter to implement statistical process control on the one or more of process steps. In one aspect, the shape of a measured mass distribution is compared with the shape of a predetermined characteristic mass distribution to monitor the process. An determined empirical relationship between a control variable of the process and the characteristic mass change may enable differences between the measured mass distribution and characteristic mass distribution to provide information about the control variable. In another aspect, the relative position of an individual measured wafer mass change in a current distribution provides information about individual wafer problems independently from general process problems.

Abstract: A semiconductor wafer metrology technique comprising performing atmospheric buoyancy compensated weighing of a wafer, in which the wafer is weighed in a substantially upright condition. A vertical or near vertical wafer orientation causes the surface area in the direction of a force (weight) sensor to be reduced compared with a horizontal wafer orientation. Hence, the electrostatic force components acting in the same direction as the wafer weight force component is reduced.

Abstract: Measuring apparatus for monitoring the position of the center of mass of a semiconductor wafer is disclosed. The apparatus includes a wafer support (14) with a ledge for supporting an edge of a wafer (2) when it is lifted at a detection point by a probe (16). The probe (16) is connected to a force sensor (18) which senses a force due to a moment of the wafer about a fulcrum (4) on the wafer support (14). Moment measurements are taken at a plurality of detection points and a processing unit calculates the position of the center of mass from the moment measurements. Changes in wafer mass distribution (e.g. due to faulty treatment steps) which cause movement of the center of mass can be detected.

Abstract: Measuring apparatus and method for monitoring fabrication of a semiconductor wafer by exciting and measuring vibrations of the wafer substrate. A measurable parameter of vibration (e.g. frequency) is indicative of mass of a vibrating region. Mass change caused by wafer treatment is reflected in changes in vibration measurements taken before and after that treatment. The apparatus includes a wafer support e.g. projecting ledge (19), a vibration exciting device e.g. contact probe (28) or pressure differential applicator, and a measurement device e.g. frequency sensor (62).

Abstract: Measuring apparatus for monitoring the position of the center of mass of a semiconductor wafer is disclosed. The apparatus includes a wafer support (14) with a ledge for supporting an edge of a wafer (2) when it is lifted at a detection point by a probe (16). The probe (16) is connected to a force sensor (18) which senses a force due to a moment of the wafer about a fulcrum (4) on the wafer support (14). Moment measurements are taken at a plurality of detection points and a processing unit calculates the position of the center of mass from the moment measurements. Changes in wafer mass distribution (e.g. due to faulty treatment steps) which cause movement of the center of mass can be detected.

Abstract: In order to determine the dielectric constant of a layer deposited on a semiconductor wafer (2), the density of the layer is obtained. To obtain that density, the wafer (2) without the layer is weighed in a weighing chamber (4) in which a weighing pan (7) supports the wafer on a weighing balance. The weight of the wafer is determined taking into account the buoyancy exerted by the air on the wafer (2). Then the layer is deposited on the wafer (2) and the weighing operation repeated. Alternatively a reference wafer may be used. If the material of the layer is known, the weight of the layer can be used to derive its density using a thickness measurement. Alternatively, if the density is known, the thickness can be obtained.

Abstract: In order to determine the dielectric constant of a layer deposited on a semiconducotr wafer (2), the density of the layer is obtained. To obtain that density, the wafer (2) without the layer is weighed in a weighing chamber (4) in which a weighing pan (7) supports the wafer on a weighing balance. The weight of the wafer is determined taking into account the buoyancy exerted by the air on the wafer (2). Then the layer is deposited on the wafer (2) and the weighing operation repeated. Alternatively a reference wafer may be used. If the material of the layer is known, the weight of the layer can be used to derive its density using a thickness measurement. Alternatively, if the density is known, the thickness can be obtained.