MeV Boron Implantation and Masking

1993 ◽  
Vol 316 ◽  
Author(s):  
James P. Lavine ◽  
A. J. Filo ◽  
D. L. Losee ◽  
P. A. Guidash ◽  
S.-T. Lee ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Silicon Dioxide ◽  
Secondary Ion Mass Spectrometry ◽  
Thick Layer ◽  
High Energy ◽  
Boron Implantation ◽  
Boron Ions ◽  
Pass Through ◽  
Metal Layers ◽  
Secondary Ion

ABSTRACTBoron depth distributions are reported for MeV implants into silicon through a variety of masking materials. Silicon is implanted with boron through a 0.1-µm-thick layer of thermally grown silicon dioxide. Secondary ion mass spectrometry (SIMS) shows the projected ranges agree within 10% with data reported in the literature and with results from the computer program TRIM. Silicon dioxide, photoresist, and metal layers are used to mask the high-energy boron implants. The SIMS results indicate that TRIM overestimates the energy loss of MeV boron ions as they pass through photoresist and/or silicon dioxide.

Hb Neuilly-Sur-Marne, a New Human Hemoglobin Variant with Ser-Asp-Leu Inserted between α86(F7) Leu and α87(F8) His: Characterization by High-Energy Collision-Induced Dissociation Liquid Secondary Ion Mass Spectrometry and Low Energy Collision-Induced Dissociation Tandem Mass Spectrometry in An Ion Trap Fitted with a Nanospray Ionization Source

2000 ◽  
Vol 6 (2) ◽  
pp. 205-211 ◽  
Author(s):  
Danielle Promé ◽  
Jean-Claude Promé ◽  
Henri Wajcman ◽  
Jean Riou ◽  
Frédéric Galactéros ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Secondary Ion Mass Spectrometry ◽  
Ion Trap ◽  
High Energy ◽  
Sequence Information ◽  
Energy Collision ◽  
Ionization Source ◽  
Nanospray Ionization ◽  
Singly Charged ◽  
Secondary Ion

Hemoglobin (Hb) Neuilly-sur-Marne is a new α-chain variant found during a systematic screening. Electrospray mass measurements showed the presence of an abnormal α-chain displaying a shift of +315 u relative to the normal value. Tryptic cleavage of this chain and molecular weight determination of the peptides indicated that the 315 u shift was located into the αT-9 peptide, the molecular weight of which is higher than 3000 Da. High-energy collision spectra of MH+ ions generated by liquid secondary ion mass spectrometry from the normal and abnormal αT-9 afforded mainly amino-terminal containing ions. They indicated that these two peptides have an identical amino acid sequence from their 1st to 25th residues, the mass increase being thus located beyond this point. Too few ions were formed to establish reliably the sequence forward. It was hypothesized that this mass shift could result from a repeated sequence since the sum of the mass of the three residues—leucine, serine and aspartic acid—preceding position 25 is exactly 315 u. To get sequence information above position 25, decomposition of multicharged species was attempted. An ion trap fitted with a nanospray ionization source was used. It produced mainly triply- and quadruply-charged ions. Decomposition of the triply-charged ion afforded a series of singly-charged Y-ions in the expected region, giving a readily interpretable sequence. It confirmed the insertion of a Ser-Asp-Leu sequence above position 25. Surprisingly, decomposition of the quadruply-charged molecular ion gave too few ions to provide sequence information in the expected region. Spectra were dominated by some multicharged Y ions arising from cleavages close to the amino end. Tandem mass spectrometry experiments were performed on the abundant Y303+ ion and produced again a singly-charged Y ion series in the suitable domain which confirmed the above result. In Hb Neuilly-sur Marne this insertion of the Ser-Asp-Leu residues. between positions α-86 and α-87 is very likely due to a slipped strand mispairing mechanism.

Deuterium Diffusion, Trapping and Stability in Buried Silicon Dioxide Layers

1998 ◽  
Vol 513 ◽  
Author(s):  
A. Boutry-Forveille ◽  
A. Nazarov ◽  
D. Ballutaud
Keyword(s):  
Mass Spectrometry ◽  
Silicon Dioxide ◽  
Isothermal Annealing ◽  
Secondary Ion Mass Spectrometry ◽  
Oxide Layers ◽  
Buried Oxide ◽  
Different Temperatures ◽  
Hydrogen Deuterium ◽  
Secondary Ion ◽  
Diffusion Profiles

ABSTRACTThe interaction of hydrogen (deuterium used as tracer) with Si-Si02-Si buried oxide layers (BOX) prepared by thermal oxidation or by oxygen implantation (SIMOX) are investigated using Secondary Ion Mass Spectrometry (SIMS) measurements combined with effusion experiments. The sample deuteration is performed at different temperatures between 150 and 300°C using a radiofrequency plasma. In SIMOX samples, the deuterium diffusion profiles analysed by SIMS show deuterium trapping on implantation defects, and deuterium diffusion in the silicon substrate by permeation through the oxide layer for temperatures higher than 250°C. The deuterium is still detected in the buried oxide layers after isothermal annealing at 600°C during 2 hours. The deuterium trapping at the siliconsilicon dioxide interfaces is analysed.

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