Title :

Large-area femtosecond laser milling of silicon employing trench analysis

Author(s) :

Bhaskar, Arun [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Philippe, Justine [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Braud, Flavie [Auteur]
Centrale de Micro Nano Fabrication - IEMN [CMNF - IEMN]
Okada, Etienne [Auteur]
Plateforme de Caractérisation Multi-Physiques - IEMN [PCMP - IEMN]
Avramovic, Vanessa [Auteur]
Plateforme de Caractérisation Multi-Physiques - IEMN [PCMP - IEMN]
Robillard, Jean-François [Auteur]
Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 [IEMN]
Durand, Cédric [Auteur]
STMicroelectronics [Crolles] [ST-CROLLES]
Gloria, Daniel [Auteur]
STMicroelectronics [Crolles] [ST-CROLLES]
Gaquière, Christophe [Auteur]
Puissance - IEMN [PUISSANCE - IEMN]
Dubois, Emmanuel [Auteur]
Microélectronique Silicium - IEMN [MICROELEC SI - IEMN]

Journal title :

Optics and Laser Technology

Pages :

106866

Publisher :

Elsevier

Publication date :

2021

ISSN :

0030-3992

English keyword(s) :

Radio-frequency (RF) integrated circuits
Silicon-oninsulator (SOI) technology
Optical profilometer characterization
Laser milling
Femtosecond laser micromachining

HAL domain(s) :

Sciences de l'ingénieur [physics]/Génie des procédés
Sciences de l'ingénieur [physics]/Optique / photonique

English abstract : [en]

A femtosecond laser is a powerful tool for micromachining of silicon. In this work, large-area laser ablation of crystalline silicon is comprehensively studied using a laser source of pulse width 300 fs at two wavelengths ...
Show more >A femtosecond laser is a powerful tool for micromachining of silicon. In this work, large-area laser ablation of crystalline silicon is comprehensively studied using a laser source of pulse width 300 fs at two wavelengths of 343 nm and 1030 nm. We develop a unique approach to gain insight into the laser milling process by means of detailed analysis of trenches. Laser scribed trenches and milled areas are characterized using optical profilometry to extract dimensional and roughness parameters with accuracy and repeatability. In a first step, multiple measures of the trench including the average depth, the volume of recast material, the average longitudinal profile roughness, the inner trench width and the volume removal rate are studied. This allows for delineation of ablation regimes and associated characteristics allowing to determine the impact of fluence and repetition rate on laser milling. In a second step, additional factors of debris formation and material redeposition that come into play during laser milling are further elucidated. These results are utilized for processing large-area (up to few mm 2) with milling depths up to 200 µm to enable the fabrication of cavities with low surface roughness at high removal rates of up to 6.9 µm 3 µs-1. Finally, laser processing in combination with XeF2 etching is applied on SOI-CMOS technology in the fabrication of radio-frequency (RF) functions standing on suspended membranes. Performance is considerably improved on different functions like RF switch (23 dB improvement in 2 nd harmonic), inductors (near doubling of Q-factor) and LNA (noise figure improvement of 0.1 dB) demonstrating the applicability of milling to radio-frequency applications.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

ANR Project :

Plateforme de traitement laser pour l'électronique flexible multifonctionnelle

Comment :

Renatech Network, Laboratoire commun STmicroelectronics - IEMN

Collections :

• Institut d'Électronique, de Microélectronique et de Nanotechnologie (IEMN) - UMR 8520

Source :

Harvested from HAL