Percussion drilling in glasses and process dynamics with femtosecond laser GHz-bursts

Lopez, John; Niane, Samba; Bonamis, Guillaume; Balage, Pierre; Audouard, Éric; Hönninger, Clemens; Mottay, Eric; Manek-Hönninger, Inka

doi:10.1364/oe.455553

Cited by 25 publications

(21 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, we noticed that detrimental extended cracks appear along the Bessel beam due to heat accumulation when the burst repetition rate is too high. A similar phenomenon has been observed in drilling experiments in the GHz-burst regime [ 47 ]. Indeed, in sodalime, for example, the burst repetition rate in the drilling experiments was limited to 10 kHz, while cutting with the Bessel beam is possible with repetition rates up to 20 kHz without HAZ appearing.…”

Section: Cutting Results and Discussionsupporting

confidence: 82%

Bessel Beam Dielectrics Cutting with Femtosecond Laser in GHz-Burst Mode

Balage,

Guilberteau,

Lafargue

et al. 2023

Micromachines

Self Cite

View full text Add to dashboard Cite

We report, for the first time to the best of our knowledge, Bessel beam dielectrics cutting with a femtosecond laser in GHz-burst mode. The non-diffractive beam shaping is based on the use of an axicon and allows for cutting glasses up to 1 mm thickness with an excellent cutting quality. Moreover, we present a comparison of the cutting results with the state-of-the-art method, consisting of short MHz-bursts of femtosecond pulses. We further illustrate the influence of the laser beam parameters such as the burst energy and the pitch between consecutive Bessel beams on the machining quality of the cutting plane and provide process windows for both regimes.

show abstract

Section: Cutting Results and Discussionsupporting

confidence: 82%

Bessel Beam Dielectrics Cutting with Femtosecond Laser in GHz-Burst Mode

Balage,

Guilberteau,

Lafargue

et al. 2023

Micromachines

Self Cite

View full text Add to dashboard Cite

show abstract

“…Other works have reported on combining MHz- and GHz-burst strategies in a biburst mode for ablation [ 31 , 32 ]. Very recently, we investigated the percussion drilling process in glasses [ 33 , 34 ] and in sapphire [ 34 ] in GHz-burst mode applying pump-probe shadowgraphy and thermal imaging [ 34 ]. Furthermore, we have shown that efficient drilling was even possible at fluences where the individual pulses within the burst have a fluence clearly lower than the ablation threshold of the material, which underlines that this processing mechanism profits from beneficial thermal accumulation.…”

Section: Introductionmentioning

confidence: 99%

Comparative Study of Percussion Drilling in Glasses with a Femtosecond Laser in Single Pulse, MHz-Burst, and GHz-Burst Regimes and Optimization of the Hole Aspect Ratio

Balage,

Lafargue,

Guilberteau

et al. 2023

Micromachines

Self Cite

View full text Add to dashboard Cite

In this contribution, we present a comparative study on top-down drilling in sodalime glass, with a femtosecond laser operating in single-pulse, MHz-burst and GHz-burst modes, respectively. We investigate the hole depth, drilling rate, and hole morphology for these three regimes while keeping the same experimental conditions. We demonstrate that, for both burst regimes, the burst length has to be adapted for optimizing the hole depth. In the GHz-burst regime, the lower the ablation rate the longer the holes. The three drilling regimes lead to different hole morphologies, where the GHz-burst mode results in the best hole quality featuring glossy inner walls and an almost cylindrical morphology. Furthermore, we obtain crack-free holes, the deepest measuring 3.7 mm in length and 25 µm in entrance diameter corresponding to an aspect ratio of 150, which is the highest aspect ratio reported thus far with femtosecond GHz-burst drilling to the best of our knowledge.

show abstract

“…1 GHz intra-burst pulse repetition frequency with a Gaussian beam. 49,50 This approach allows for tuning the burst envelope as well as burst energy and duration. While the method can produce very high aspect ratio holes in different types of glass (∼30 µm diameter holes with 30:1 aspect ratio in soda lime glass and 70:1 in fused silica 51 ), the process requires tens of bursts to initiate drilling, a low inter-burst pulse repetition frequency to reduce thermal effects and sidewall collapse, and a very long drill time.…”

Section: Laser-based Methods For Forming Tgvsmentioning

confidence: 99%

Rapid and high throughput formation of through glass vias

Schrauben,

Matsumoto,

Lin

et al. 2024

Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XXIX

View full text Add to dashboard Cite

Interest in glass for integrated circuit (IC) packaging and interposer applications has accelerated in recent years, due to its favorable mechanical and electrical properties compared to current advanced materials. This report describes our recent results on through glass via (TGV) drilling, utilizing a novel process employing a single laser source with an engineered pulse duration, pulse repetition frequency, and average power to rapidly form TGVs in 50 and 100 µm thick glass. The process forms TGVs with a ∼10 µm diameter with zero taper, smooth sidewalls and minimal splash; the dimensions of these TGVs meet the requirements for next-generation interposers to replace through silicon vias. Unlike Bessel beam based processes, this process is compatible with high bandwidth beam steering technologies (galvanometers and acousto-optic deflectors (AODs)), enabling an industrially viable throughput in high-density drill patterns of more than 10000 vias per second. The formation dynamics of the TGVs are elucidated using multiphase simulations and in-situ spectroscopic methods. Stress mitigation in the fully-formed TGVs is explored through annealing studies; an alternate approach utilizes heating of the glass substrate during the laser processing to minimize stress formation during the drilling process. Both methods are shown to mitigate embedded stress and avoid cracking.

show abstract

Percussion drilling in glasses and process dynamics with femtosecond laser GHz-bursts

Cited by 25 publications

References 15 publications

Bessel Beam Dielectrics Cutting with Femtosecond Laser in GHz-Burst Mode

Bessel Beam Dielectrics Cutting with Femtosecond Laser in GHz-Burst Mode

Comparative Study of Percussion Drilling in Glasses with a Femtosecond Laser in Single Pulse, MHz-Burst, and GHz-Burst Regimes and Optimization of the Hole Aspect Ratio

Rapid and high throughput formation of through glass vias

Contact Info

Product

Resources

About