Detection of crystalline defects in Si/SiGe superlattices towards 3D-DRAM applications

M. Beggiato; D. Cerbu; R. Loo; W. Sun; A. Moussa; G. Bast; K. Fukaya; C. Beral; A.-L. Charley; N. Janardan; A. Cross; G. Lorusso; M. Isawa; A. Belmonte; G. Sankar Kar; J. Bogdanowicz

doi:10.1117/12.3011279

9 April 2024 Detection of crystalline defects in Si/SiGe superlattices towards 3D-DRAM applications

M. Beggiato, D. Cerbu, R. Loo, W. Sun, A. Moussa, G. Bast, K. Fukaya, C. Beral, A.-L. Charley, N. Janardan, A. Cross, G. Lorusso, M. Isawa, A. Belmonte, G. Sankar Kar, J. Bogdanowicz

Author Affiliations +

Proceedings Volume 12955, Metrology, Inspection, and Process Control XXXVIII; 129551F (2024) https://doi.org/10.1117/12.3011279
Event: SPIE Advanced Lithography + Patterning, 2024, San Jose, California, United States

Abstract

Si/SiGe heterostructures are gaining traction as a starting template in applications such as Gate-All-Around Field-Effect Transistor (GAAFET), complementary FET (CFET), and 3-dimensional dynamic random access memory (3D-DRAM), where the SiGe alloy plays the role of sacrificial material for channel release. However, the formation of crystalline defects (e.g. crosshatch) in the epitaxially grown layers plays a critical part in determining the overall device performance. As such, it is key to be able to control the defectivity level using large surface area inspection techniques. The challenge of such inspection is that it must combine a high enough throughput to detect low-density defects together with sensitivity to nanometer size defects. In addition, the technique should also be able to distinguish these elongated one-dimensional crystalline defects from other types of defects. In this study, we investigate the impact of the number of Si/SiGe bilayers on the crystal defect distribution utilizing a combined approach of optical inspection and extensive e-beam review for both qualitative and quantitative defect characterization. In-line optical inspection techniques revealed that the crosshatch density and distribution varied significantly with the number of Si/SiGe bilayers. These observations were then confirmed by high-resolution e-beam review coupled with image analysis and signal processing to enable crosshatch quantification. Our approach considers an initial investigation on thin Si/SiGe bilayers (up to ~5x bilayers) and is further extended to thick stacks (up to 60x bilayers) to evaluate the capability of optical inspection as the high-throughput reference technique. In conclusion, this study aims to develop a methodology to investigate the crosshatch density in Si/SiGe superlattices, using optical inspection and e-beam review as main characterization tools. These techniques offer valuable insights in terms of defect distribution at the wafer level for the design and fabrication of next-generation semiconductor devices.

Conference Presentation

(2024) Published by SPIE. Downloading of the abstract is permitted for personal use only.

Citation Download Citation

M. Beggiato, D. Cerbu, R. Loo, W. Sun, A. Moussa, G. Bast, K. Fukaya, C. Beral, A.-L. Charley, N. Janardan, A. Cross, G. Lorusso, M. Isawa, A. Belmonte, G. Sankar Kar, and J. Bogdanowicz "Detection of crystalline defects in Si/SiGe superlattices towards 3D-DRAM applications", Proc. SPIE 12955, Metrology, Inspection, and Process Control XXXVIII, 129551F (9 April 2024); https://doi.org/10.1117/12.3011279

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available