One challenge for volume manufacturing of 4H-SiC devices is the state-of-the-art wafer dicing technology – the mechanical blade dicing which suffers from high tool wear and low feed rates. In this paper we discuss Thermal Laser Separation (TLS) as a novel dicing technology for large scale production of SiC devices. We compare the latest TLS experimental data resulting from fully processed 4H-SiC wafers with results obtained by mechanical dicing technology. Especially typical product relevant features like process control monitoring (PCM) structures and backside metallization, quality of diced SiC-devices as well as productivity are considered. It could be shown that with feed rates up to two orders of magnitude higher than state-of-the-art, no tool wear and high quality of diced chips, TLS has a very promising potential to fulfill the demands of volume manufacturing of 4H-SiC devices.
This paper presents improvements in resizing single crystalline Si wafers by using the dicing technology "Thermal Laser Separation" (TLS). Results of this work support the general need to resize wafers to smaller diameters and will play an important role during the transition to larger wafer diameters as currently projected in the ITRS for 450 mm: Wafers of new sizes have to be easily adapted to fit, e.g., currently available metrology tools. TLS process parameters were developed for resizing Si wafers and to produce demo wafers which were analyzed and compared with current state of the art techniques plasma etching, laser ablation and mechanical wafer sawing. For the first time, circular cuts with diameters up to 300 mm were produced out of 450 mm ( thickness: 925 mu m) single crystalline Si wafers with TLS. The TLS process results in two important benefits for resized wafers: First, the edge of the new wafer is of higher quality than the edges produced by state of the art resizing techniques. Second, the TLS process is up to 24 times faster than known resizing processes
Based on recent progress on laser-based wafer dicing equipment and process, the partners adixen, Fraunhofer IISB and JENOPTIK investigated the use of a vacuum based decontamination process to dry and to decontaminate the substrate surface of the diced wafers from water residuals, which are a side-effect of the TLS (thermal laser separation) approach. The decontamination process was achieved by using an adixen vacuum drying module prototype further to the JENOPTIK TLS dicing process. Within the frame of the European collaborative project SEAL, supported by the European Commission, experimental assessment was conducted by Fraunhofer IISB (research institution) together with JENOPTIK and Adixen.
With the gaining demand for SiC semiconductor devices it is more and more challenging to meet the requirements for SiC volume production with the state of the art wafer dicing technology. In order to overcome this challenge the laser based dicing technology Thermal Laser Separation (TLS-DicingTM) was assessed for SiC volume production within the European project SEA4KET. This paper presents the key results of this project. It could be demonstrated that the demand of SiC volume production regarding throughput and cost as well as edge quality and electrical performance of diced chips can be met with TLS-DicingTM.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.