Query: Stealth Dicing sic

Candidate papers:

abstract: Current methods of wafer cutting for silicon carbide (SiC) substrates by semiconductor and chip packaging fabs are prohibiting high volume production required to meet growing demand for more efficient electronic devices Due to the high hardness and brittleness of SiC, chipping (front and back) cracking and micro cracking, cycle time and cost are the main challenges The industry is looking at other cutting technologies such as laser cutting, micro Jet dicing and plasma dicing to address the manufacturing issues Alternative solutions such as laser ablation, stealth dicing and plasma dicing, have their problems, especially in running cost Mechanical dicing with improved platform design could address issues related cut quality, cycle time and lower overall running cost to enable future high volume manufacturing
title: Accelerating Silicon Carbide Power Electronics Devices into High Volume Manufacturing with Mechanical Dicing System
year: 2016

abstract: Recently many issues came up when using conventional dicing methods. Such conventional methods are mechanical sawing (blade dicing) or laser dicing or stealth dicing. Relevant applications are thin wafers, brittle materials and wafer singulation for very small devices or LED or discretes. Plasma dicing is a recommended method to overcome many challenges of wafer separation. Damage free, water free, particle free and high throughput dicing can be realized by using plasma trench etch (dry etch) technology for dicing. Several technical and equipment aspects will be presented and discussed accordingly. Plasma dicing technology can provide solutions for high rate dicing, beautiful chip shape without any chipping and high bonding strength. Future challenges such as SiC dicing or GaN on Silicon dicing will be discussed.
author_names: Reinhard Windemuth
title: Plasma dicing for thin wafers
venue: 2015 European Microelectronics Packaging Conference (EMPC)
year: 2015

abstract: Mechanical blade dicing is a state of the art technique for the chip separation of SiC devices. Due to the hardness of SiC this technique suffers from low feed rate and high wear of the diamond coated dicing blade, resulting in the risk of uncontrolled tool breakage during the dicing process. With the upcoming transition to 150 mm diameter of SiC wafers this technique will most probably reach its limit. For dicing SiC wafers of those diameters on a productive scale three alternative dicing technologies are considered in this paper: ablation laser dicing, Stealth Dicing and Thermal Laser Separation. All these methods are based on laser processing. The benefits of these technologies are discussed in detail and compared to the classical mechanical diamond blade dicing, including a brief summary of first experimental results on each of the three laser dicing technologies.
author_names: Karl Otto Dohnke

Korbinian Kaspar

Dirk Lewke
title: Comparison of Different Novel Chip Separation Methods for 4H SiC
year: 2015

abstract: We report on a one step method for cutting 250 um thick quartz plates using highly focused ultrashort laser pulses with a duration of 200 fs and a wavelength of 1030 nm. We show that the repetition rate, the scan speed, the pulse overlap and the pulse energy directly influence the cutting process and quality. Therefore, a suitable choice of these parameters was necessary to get single pass stealth dicing with neat and flat cut edges. The mechanism behind the stealth dicing process was ascribed to tensile stresses generated by the relaxation of the compressive stresses originated in the laser beam focal volume during irradiation in the bulk material. Such stresses produced micro fractures whose controlled propagation along the laser beam path led to cutting of the samples.
author_names: Caterina Gaudiuso

Annalisa Volpe

Antonio Ancona
title: One Step Femtosecond Laser Stealth Dicing of Quartz
venue: Micromachines
year: 2020

abstract: We report on a damage less singulation technique using Stealth Dicing (SD) of ultra thin wafers. This paper describes how we minimized the damage using highly sensitive Test Element Group (TEG) wafers with patterned aluminum lines. We developed a TEG wafer, having multiple wiring lines of Ti/Al layers, to monitor laser damage. The wiring lines were designed so that a change in wiring resistance caused by scattered light could be measured. Also, in order to measure the position of the generated scatter damage, the line/space ratio (L/S) of the monitor wiring was designed to be 1 mm/1 mm. In this experiment, IR OBIRCH and STEM analyses were performed to identify the details of the laser damage on the wiring. In addition, two types of lasers (wavelengths: 1099 nm and 1342 nm) were used to evaluate the effect of the transmittance in silicon on the processing results. Laser damage evaluation was carried out on the basis of parameters such as the laser processing power and laser focus position (distance from the device side) We confirmed that laser damage was prevented and that damage free singulation could be achieved by optimizing the processing conditions using a laser with a wavelength of 1099 nm. By applying this SD technology, the width of the dicing street can be shrunk to 1/4 compared with the conventional blade dicing.
author_names: Natsuki Suzuki

Tomoji Nakamura

Yuta Kondo

Shimpei Tominaga

Kazuhiro Atsumi

Takayuki Ohba
title: Damage Less Singulation of Ultra Thin Wafers using Stealth Dicing
venue: 2020 IEEE 70th Electronic Components and Technology Conference (ECTC)
year: 2020

abstract: This paper describes the reduction of singulation defects and die strength enhancement in Stealth Dicing before Grinding process. The process was carried on wafers which are 710mm in thickness at a laser wavelength of 1342nm, after the SD (stealth dicing) process, wafers need to be grinded to 60mm with BG (back grinding) method. After SD, laser scattered damage scattered damage and cleavage fracture have been analyzed. After BG, the ratios of singulative dies that have different defects such as silicon dust and kerf defect have been calculated. In this paper, the optimization of the SD process has led to the reduction of the SD related defects and die strength has also been improved. The kerf loss after SD has been calculated and 100% kerf has been achieved. Besides, die strength has been increased by 19.53% which can illustrate the high quality of laser singulation.
author_names: Yitong Xie

Xundi Zhang

Chenlin Yang

Liming Gao

Ming Li
title: Effects of Stealth Dicing Parameters on Singulation Defects and Die Strength
venue: 2020 21st International Conference on Electronic Packaging Technology (ICEPT)
year: 2020

abstract: The adhesion between metal and polymer layer was studied using four point bending tests. It was shown that as the annealing temperature increased, oxidation binding increased, which decreased adhesion and reduced the $G_{c} value. A new four point bending test sample prepared using the stealth dicing method with a 100% success rate was proposed for the first time. With samples prepared with stealth dicing, the region where crack extension occurred was smaller after the stress test. Less crack extension generated less loading on the samples. Owing to the coefficient of thermal expansion (CTE) mismatch after increasing the temperature in a highly accelerated stress test (HAST) a void formed in stealth dicing was made close to the interface between the silicon layer and the polymer layer after the stress test, and less crack extension occurred compared with samples kept at room temperature. The smaller loading force guarantees much more stable measurement with a higher success rate after the stress tests. The stealth dicing method can be applied to other structures, such as redistribution layers (RDLs)
author_names: Yi-Lun Yang

Hiroyuki Ito

Yo Suk Kim

Takayuki Ohba

Kuan-Neng Chen
title: Evaluation of Metal/Polymer Adhesion and Highly Reliable Four Point Bending Test Using Stealth Dicing Method in 3 D Integration
venue: IEEE Transactions on Components, Packaging and Manufacturing Technology
year: 2020

abstract: We report on the development of an ultrafast beam shaper capable of generating Bessel beams of high cone angle that maintain a high intensity hot spot with subwavelength diameter over a propagation distance in excess of 8 mm. This generates a high intensity focal region with extremely high aspect ratio exceeding 10 000:1. The absence of intermediate focusing in the shaper allows for shaping very high energies, up to Joule levels. We demonstrate a proof of principle application of the Bessel beam shaper for stealth dicing of thick glass, up to 1 cm. We expect that this high energy Bessel beam shaper will have applications in several areas of high intensity laser physics.We report on the development of an ultrafast beam shaper capable of generating Bessel beams of high cone angle that maintain a high intensity hot spot with subwavelength diameter over a propagation distance in excess of 8 mm. This generates a high intensity focal region with extremely high aspect ratio exceeding 10 000:1. The absence of intermediate focusing in the shaper allows for shaping very high energies, up to Joule levels. We demonstrate a proof of principle application of the Bessel beam shaper for stealth dicing of thick glass, up to 1 cm. We expect that this high energy Bessel beam shaper will have applications in several areas of high intensity laser physics.
author_names: Remi Meyer

Luc Froehly

R Giust

J Del Hoyo

Luca Furfaro

Cyril Billet

Francois Courvoisier
title: Extremely high aspect ratio ultrafast Bessel beam generation and stealth dicing of multi millimeter thick glass
venue: Applied Physics Letters
year: 2019

abstract: In this study, a sandwich structure (silicon/polymer/silicon) was prepared to demonstrate the adhesion strength between polymer and silicon layers using a four point bending system. For the first time, the stealth dicing (SD) method was applied to the silicon layer to generate an initial crack, and the SD method was compared with the traditional method of forming a trench by blade dicing. From the experimental results, the SD method improved the test yield and showed a lower level of sudden force drop. As a result, SD is a highly reliable way to measure the adhesion strength using a four point bending system.
author_names: Yi-Lun Yang

Jialong Liu

Guan Wei Chen

Shoichi Kodama

Kyosuke Kobinata

Kuan-Neng Chen

Hiroyuki Ito

Young suk Kim

Takayuki Ohba
title: Highly Reliable Four Point Bending Test Using Stealth Dicing Method for Adhesion Evaluation
venue: 2019 International Conference on Electronics Packaging (ICEP)
year: 2019

abstract: In flip chip mounting process, chip is fragile since chip is not protected by mold resin. It is known that the backside coating tape has been used widely to correspond to blade dicing. We had developed a release sheet integrated backside coating tape corresponding to blade dicing for a thin wafer. On the other hand, stealth dicing becomes popular to prevent chipping. In this study, we investigate the process of release sheet integrated backside coating tape corresponding to stealth dicing. we evaluate process consisting of stealth dicing, mount, laser marking, cool expanding, heat shrinking, heat curing and pick up. As a result, it is found that it is possible to manufacture a chip with backside coating layer in lower height expanding by optimization of the base film material of release sheet and expanding condition.
author_names: Daisuke Yamamoto

Naoya Saiki

Shinya Takyu
title: Release Sheet Integrated Backside Coating Tape Corresponding to Stealth Dicing
venue: 2019 IEEE CPMT Symposium Japan (ICSJ)
year: 2019