BT IMAGING PTY LTD. Patent applications |
Patent application number | Title | Published |
20140212020 | PHOTOLUMINESCENCE IMAGING OF DOPING VARIATIONS IN SEMICONDUCTOR WAFERS - Photoluminescence-based methods are presented for facilitating alignment of wafers during metallisation in the manufacture of photovoltaic cells with selective emitter structures, and in particular for visualising the selective emitter structure prior to metallisation. In preferred forms the method is performed in-line, with each wafer inspected after formation of the selective emitter structure to identify its location or orientation. The information gained can also be used to reject defective wafers from the process line or to identify a systematic fault or inaccuracy with the process used to form the patterned emitter structure. Each wafer can additionally be inspected via photoluminescence imaging after metallisation, to determine whether the metal contacts have been correctly positioned on the selective emitter structure. The information gained after metallisation can also be used to provide feedback to the upstream process steps. | 07-31-2014 |
20140191776 | METHOD AND SYSTEM FOR TESTING INDIRECT BANDGAP SEMICONDUCTOR DEVICES USING LUMINESCENCE IMAGING - Embodiments of methods and systems for identifying or determining spatially resolved properties in indirect bandgap semiconductor devices such as solar cells are described. In one embodiment, spatially resolved properties of an indirect bandgap semiconductor device are determined by externally exciting the indirect bandgap semiconductor device to cause the indirect bandgap semiconductor device to emit luminescence ( | 07-10-2014 |
20140039820 | QUANTITATIVE SERIES RESISTANCE IMAGING OF PHOTOVOLTAIC CELLS - Luminescence-based methods are disclosed for determining quantitative values for the series resistance across a photovoltaic cell, preferably without making electrical contact to the cell. Luminescence signals are generated by exposing the cell to uniform and patterned illumination with excitation light selected to generate luminescence from the cell, with the illumination patterns preferably produced using one or more filters selected to attenuate the excitation light and transmit the luminescence. | 02-06-2014 |
20130129187 | PERSISTENT FEATURE DETECTION - Methods are presented for improved detection of persistent or systematic defects induced during the manufacture of a product. In particular, the methods are directed to the detection of defects induced systematically in the manufacture of photovoltaic cells and modules. Images acquired from a number of samples are combined, enhancing the systematic defects and suppressing random features such as variations in material quality. Once a systematic defect is identified, steps can be taken to locate and rectify its cause. | 05-23-2013 |
20130062536 | Illumination Systems and Methods for Photoluminescence Imaging of Photovoltaic Cells and Wafers - Methods are presented for analysing semiconductor materials ( | 03-14-2013 |
20130043405 | In-Line Photoluminescence Imaging of Semiconductor Devices - Methods and systems are presented for acquiring photoluminescence images ( | 02-21-2013 |
20120181452 | SEPARATION OF DOPING DENSITY AND MINORITY CARRIER LIFETIME IN PHOTOLUMINESCENCE MEASUREMENTS ON SEMICONDUCTOR MATERIALS - Methods are presented for separating the effects of background doping density and effective minority carrier lifetime on photoluminescence (PL) generated from semiconductor materials. In one embodiment the background doping density is measured by another technique, enabling PL measurements to be analysed in terms of effective minority carrier lifetime. In another embodiment the effective lifetime is measured by another technique, enabling PL measurements to be analysed in terms of background doping density. In yet another embodiment, the effect of background doping density is removed by calculating intensity ratios of two PL measurements obtained in different spectral regions, or generated by different excitation wavelengths. The methods are particularly useful for bulk samples such as bricks or ingots of silicon, where information can be obtained over a much wider range of bulk lifetime values than is possible with thin, surface-limited samples such as silicon wafers. The methods may find application in solar cell manufacturing for improving the manufacture of silicon ingots and bricks, or for providing a cutting guide for wafering. | 07-19-2012 |
20110188733 | Photovoltaic Cell Manufacturing - Disclosed is a method ( | 08-04-2011 |
20110117681 | THIN FILM IMAGING METHOD AND APPARATUS - Methods and apparatus are presented for monitoring the deposition and/or post-deposition processing of semiconductor thin films using photoluminescence imaging. The photoluminescence images are analysed to determine one or more properties of the semiconductor film, and variations thereof across the film. These properties are used to infer information about the deposition process, which can then be used to adjust the deposition process conditions and the conditions of subsequent processing steps. The methods and apparatus have particular application to thin film-based solar cells. | 05-19-2011 |
20110025839 | WAFER IMAGING AND PROCESSING METHOD AND APPARATUS | 02-03-2011 |
20100025588 | DETERMINING DIFFUSION LENGTH OF MINORITY CARRIERS USING LUMINESCENCE | 02-04-2010 |
20090206287 | METHOD AND SYSTEM FOR TESTING INDIRECT BANDGAP SEMICONDUCTOR DEVICES USING LUMINESCENCE IMAGING - Embodiments of methods and systems for identifying or determining spatially resolved properties in indirect bandgap semiconductor devices such as solar cells are described. In one embodiment, spatially resolved properties of an indirect bandgap semiconductor device are determined by externally exciting the indirect bandgap semiconductor device to cause the indirect bandgap semiconductor device to emit luminescence ( | 08-20-2009 |
20090051914 | Method and System for Inspecting Indirect Bandgap Semiconductor Structure | 02-26-2009 |