Optimized Laser Thermal Annealing on Germanium for High Dopant Activation and Low Leakage Current

Maryam Shayesteh (1) , Dan O' Connell (1) , Farzan Gity (1) , Philip Murphy-Armando (1) , Ran Yu , Karim Huet (2) , Inès Toque-Tresonne (2) , Fuccio Cristiano (3) , Simona Boninelli (4) , Henrik Hartmann Henrichsen , Peter Nielsen (5) , Dirch Hjorth Petersen , Ray Duffy (1)

1 Tyndall National Institute [Cork]
2 SCREEN-LASSE
3 LAAS-MPN - Équipe Matériaux et Procédés pour la Nanoélectronique
4 IMM - Istituto per la Microelettronica e Microsistemi [Catania]
5 AAU - Aalborg University [Denmark]

In this paper, state-of-the-art laser thermal anneal-ing is used to fabricate Ge diodes. We compared the effect of laser thermal annealing (LTA) and rapid thermal annealing (RTA) on dopant activation and electrical properties of phosphorus and Arsenic-doped n+/p junctions. Using LTA, high carrier concentration above 10 20 cm −3 was achieved in n-type doped regions, which enables low access resistance in Ge devices. Furthermore, the LTA process was optimized to achieve a diode I ON /I OFF ratio ∼10 5 and ideality factor (n) ∼1.2, as it allows excellent junction depth control when combined with optimized implant conditions. On the other hand, RTA revealed very high I ON /I OFF ratio ∼10 7 and n ∼1, at the cost of high dopant diffusion and lower carrier concentrations which would degrade scalability and access resistance.

Mots clés: Ge; laser thermal annealing (LTA); leakage current; n+/p junction

Domaines: Physique [physics]; Science des matériaux [cond-mat.mtrl-sci]; Sciences de l'ingénieur [physics]; Matériaux; Micro et nanotechnologies/Microélectronique

Maryam Shayesteh, Dan O' Connell, Farzan Gity, Philip Murphy-Armando, Ran Yu, et al.. Optimized Laser Thermal Annealing on Germanium for High Dopant Activation and Low Leakage Current. IEEE Transactions on Electron Devices, 2014, 61 (12), pp.4047 - 4055. ⟨10.1109/ted.2014.2364957⟩. ⟨hal-01921394⟩