Barium, strontium and bismuth contamination in CMOS processes
Research output: Contribution to book/conference proceedings/anthology/report › Conference contribution › Contributed › peer-review
Contributors
Abstract
Contamination aspccts of ferroelectric (SrBi2Ta2O9) and high diclcctric constant (Ba,Sr)TiO3 materials in CMOS processes were investigated in this paper, TXRF, VPD-TXRF, and ToF-SIMS were used to study the desorption and diffusion properties of Sr. Bi. and Ba contamination on Si at 800°C anneals. Sr and Ba dissolve in native or thermal oxide, and only very small quantities diffuse into silicon, whereas Bi - if annealed in N2 - evaporates and its diffusion into silicon cannot be detected; in case of O2 annealing, all Bi is incorporated in the thermal oxide grown. The diffusion constants for Ba and Sr in Si are in the order of I O-16 cm2/s at 800°C. Measurements of minority carrier recombination lifetime of contaminated n and p-type wafers showed no drastic decrease in lifetime for the three elements up to contamination levels of 1014 at/cm2 The leakage currents of diodes contaminated after device processing by Ba, Sr. and Bi up with concentrations between 1012 and 1014" at/cm2 have nearly the same value as for non-contaminatcd diodes. This leads to the conclusion that Sr. Bi. and Ba do not present a drastic risk on minority carrier lifetime and diode leakage current in future Gbit-scale non-volatile Ferroelectric Random Access Memories (NVFeRAMs) or high diclectric constant Dynamic Random Access Memories (high k-DRAMs) generatioas.
Details
Original language | English |
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Title of host publication | Ultra Clean Processing of Silicon Surfaces 2000 |
Editors | Marc Heyns, Paul Mertens, Marc Meuris |
Publisher | Trans Tech Publications Ltd |
Pages | 9-14 |
Number of pages | 6 |
ISBN (print) | 9783908450573 |
Publication status | Published - 2001 |
Peer-reviewed | Yes |
Externally published | Yes |
Publication series
Series | Solid State Phenomena |
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Volume | 76-77 |
ISSN | 1012-0394 |
Conference
Title | 5th International Symposium on Ultra Clean Processing of Silicon Surfaces, UCPSS 2000 |
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Duration | 18 - 20 September 2000 |
City | Ostend |
Country | Belgium |
External IDs
ORCID | /0000-0003-3814-0378/work/156338384 |
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Keywords
ASJC Scopus subject areas
Keywords
- FeRAMs, High-K DRAMs, Metal contamination