51 results about "Surface photovoltage" patented technology

A method and apparatus for measuring damage of an ion implanted semiconductor wafer during semiconductor processing. The method includes the steps of conveying the wafer such that a surface of the wafer is substantially parallel to a surface photovoltage electrode of a head assembly during the semiconductor processing and exposing at least a portion of said wafer to light having a wavelength, and an intensity and modulating the light intensity at a predefined frequency. The method also includes the step of varying the frequency of the light intensity modulation and detecting the surface photovoltage in response to light modulated at the various frequencies using the surface photovoltage electrode. The method then calculates an electrical property of the wafer from the photovoltage induced at the surface of the wafer at each of the light intensity modulation frequencies.

There is provided a method for calculating a more accurate metal impurity concentration contained in a silicon wafer by correcting measured values with a calibration based on a dependent relationship of the minority carrier diffusion length with a period of time elapsing from the activation to the actual measurement, an electric resistivity, and a temperature if there is such a relationship, in the measurement of the metal impurity concentration by utilizing the surface photovoltage. In the calibration step, such dependent relationship may be obtained by utilizing the metal impurity concentration measured by methods of different principles and actually measured values are corrected in light of the dependent relationship in the measuring step such that the metal impurity concentration is measured more accurately.

Disclosed herein are various methods of determining characteristics of doped regions on device wafers, and a system for accomplishing same. In one illustrative embodiment, the method includes providing a device substrate comprising a plurality of masked areas, a plurality of unmasked areas, and at least one doped region formed in the substrate, determining a ratio between the unmasked areas and the masked areas for the device substrate, illuminating an area of the device substrate comprising the masked areas, the unmasked areas, and at least one doped region, and measuring an induced surface photovoltage of the device substrate while accounting for the ratio of the unmasked areas and the masked areas of the device substrate. In another illustrative embodiment, the method includes providing an SOI substrate comprised of an active layer, the active layer having a thickness, illuminating an area of the substrate using a light source having a wavelength that is sufficiently long such that an excited region created in the active layer due to the illumination does not extend beyond the thickness of the active layer, and measuring an induced surface photovoltage resulting from the illumination.

There is provided a silicon wafer surface defect evaluation method capable of readily detecting a region where small crystal defects exist, the evaluation method comprising: a rapid heat treatment step of a silicon wafer from a silicon single-crystal ingot in an atmosphere which can nitride silicon at a temperature elevating speed of 10 to 150° C. / second from a room temperature to temperatures between not lower than 1170° C. and less than a silicon melting point, holding the silicon wafer at the processing temperature for 1 to 120 seconds and then cooling the silicon wafer to the room temperature at a temperature lowering speed of 10 to 100° C. / second; and a step of using a surface photo voltage method to calculate a minority carrier diffusion length on the wafer surface, thereby detecting a region on the wafer surface in which small COP's which cannot be detected at least by a particle counter exist.

A method of measuring a diffusion length of a minority carrier in a silicon wafer by a surface photovoltage method including irradiating the surface-treated silicon wafer with ultraviolet radiation in an oxygen-containing atmosphere, and measuring a diffusion length of a minority carrier in a silicon wafer by a surface photovoltage method.

The present invention discloses an apparatus and method for real-time, on-line testing of semiconductor wafers during the manufacturing process. In one embodiment, an apparatus includes a detector assembly within a semiconductor wafer processing line. As each wafer travels into proximity with the detector assembly, a modulated light source within the detector assembly having a predetermined wavelength and modulation frequency illuminates the wafer. Sensors in the detector assembly measure the surface photovoltage induced by the modulated light. A computer then uses the sensed surface photovoltage to determine various electrical properties of the wafer.

A method and apparatus for measuring damage of an ion implanted semiconductor wafer during semiconductor processing. The method includes the steps of conveying the wafer such that a surface of the wafer is substantially parallel to a surface photovoltage electrode of a head assembly during the semiconductor processing and exposing at least a portion of the wafer to light having a wavelength, and an intensity and modulating the light intensity at a predefined frequency. The method also includes the step of varying the frequency of the light intensity modulation and detecting the surface photovoltage in response to light modulated at the various frequencies using the surface photovoltage electrode. The method then calculates an electrical property of the wafer from the photovoltage induced at the surface of the wafer at each of the light intensity modulation frequencies.

An apparatus and method for the real-time, in-line testing of semiconductor wafers during the manufacturing process. In one embodiment the apparatus includes a probe assembly within a semiconductor wafer processing line. As each wafer passes adjacent the probe assembly, a source of modulated light, within the probe assembly, having a predetermined wavelength and frequency of modulation, impinges upon the wafer. A sensor in the probe assembly measures the surface photovoltage induced by the modulated light. A computer then uses the induced surface photovoltage to determine various electrical characteristics of the wafer.

A method of determining a diffusion length of a minority carrier in a material which includes applying a first excitation light having a first photon flux to a material, measuring a first surface photo voltage resulting from the application of the first excitation light, applying a second excitation light having a second photon flux to the material, measuring a second surface photo voltage resulting from the application of the second excitation light, applying a third excitation light having a third photon flux, having a predetermined ratio to the first photon flux, to the material, measuring a third surface photo voltage resulting from the application of the third excitation light, determining a diffusion length of a minority carrier in the material based on the measured first, second and third surface photo voltages.

An apparatus and method for the real-time, in-line testing of semiconductor wafers during the manufacturing process. In one embodiment the apparatus includes a probe assembly within a semiconductor wafer processing line. As each wafer passes adjacent the probe assembly, a source of modulated light, within the probe assembly, having a predetermined wavelength and frequency of modulation, impinges upon the wafer. A sensor in the probe assembly measures the surface photovoltage induced by the modulated light. A computer then uses the induced surface photovoltage to determine various electrical characteristics of the wafer.

The invention discloses a surface photovoltage method based semiconductor material parameter testing device and testing method. The testing device comprises a casing, a cantilever, a measuring probe and a sample bench, wherein the measuring probe is internally provided with an infrared laser and a sensing electrode slice; a pulse light source driver is positioned inside the casing; a semiconductor material sample to be tested is arranged on the sampling bench; the measuring probe is right over the sample to be tested; the sensing electrode slice is connected with a charge amplifier through a coaxial cable wire; and the infrared laser is connected with the pulse light source driver through a two-core shield wire. The testing method is as follows: the pulse light emitted by the infrared laser is vertically irradiated on the sample, the sensing electrode slice receives the static charge generated by the weak photovoltage on the surface of the sample for transmitting to the input end of the charge amplifier, and a liquid crystal display screen displays the conductive type and resistivity / sheet resistance values of the sample to be tested after the static charge is processed by a signal processing circuit. The testing device provided by the invention has the advantages of small volume, light weight, small power consumption and low cost.