Image gallery
Below we have shown several snapshots obtained from our simulations. Click on the thumbnail to see a high-resolution image.
Our cover graphics
Sputtering - artistic visions
Sputtering of frozen gases
70 eV Ar -> Ar
Even particles with such low kinetic energy can stimulate efficient sputtering of weakly bound materials.
1 keV Ar -> Ar
Side view. A 1.5nm-wide cut centered at the projectile impact point is shown
Top view. Images are colored according to the particle depth. Scale spans from red (<4nm below the original surface) to dark blue (>3nm above the original surface)
1 keV Ar impact at frozen Ar leads to a formation of macroscopic crater.
Sputtering of metals
4 keV Ar -> Ag{111}
Atoms located in the topmost layer are mainly ejected.
Sputtering of Ag{111} by Ga and C60
Sputtering of Ag{111} by impact of 15 keV Ga projectile.
Snapshots are collected at 0.0, 3.0 and 7.5 ps. Atoms are colored according to their position (depth) in the perfect crystal: blue - layers 1 and 2, red - layers 3 and 4, green - layers 5 and 6, light blue - layers 7 and 8.
Sputtering of Ag{111} by impact of 15 keV C60 projectile.
Snapshots are collected at 0.0, 3.0 and 7.5 ps.
15 keV Ga impact leads to lower sputtering yield than 15 keV C60. At the same time it causes more significant alteration of the bombarded crystal. The increase of the kinetic energy of the C60 projectile leads to a larger crater. The volume of the crater increases mostly due to increase of its diameter not depth.
Molecular emission induced by cluster bombardment
Intact molecules are ejected by catapult mechanism
Examples:
Sputtering of PS61 molecule adsorbed at Ag{111} by impact of 20 keV C60 projectile.
Snapshots are collected at 0.0, 3.0 and 7.5 ps.
Sputtering of PS4 molecules adsorbed at Ag{111} by impact of 15 keV C60 projectile.
Snapshots are collected at 0.0, 1.0, 3.0 and 7.5 ps.
Molecular emission from thin organic layers induced by impact of atomic projectiles
Organic molecules bound to the surface by physisorption are ejected mainly due to collisions with departing substrate atoms Two general mechanisms leading to ejection of intact molecules were identified:
a) adsorbed molecule is hit by a departing single atom
This mechanism occurs at early stages of development of collision cascade and leads to ejection of energetic molecules.
b) adsorbed molecule is gently uplifted by a collective action of several substrate atoms
This mechanism occurs at later stages of development of collision cascade and leads to ejection of slow molecules. This mechanism is known to be responsible for ejection of large intact organic molecules.
Examples:
Sputtering of PS4 molecules physisorbed at Ag{111} surface by 15 keV Ga
Sputtering of thin benzene overlayer physisorbed at Ag{111} surface by 15 keV Ga
Sputtering of thin benzene overlayer physisorbed at Ag{111} surface by 4 keV Ar
Surface of a multilayer benzene just before the impact of 4 keV Ar
Sputtering sequence of benzene molecules ejected from 3 layer system irradiated by 4 keV Ar. Top view.
Lateral damage generated in multilayer benzene irradiated by 4 keV Ar
Molecules are colored according to in a following way: Orange - molecules from the topmost layer, purple - molecules from the second layer, red - molecules located just above the metal substrate. Snapshot obtained 13 ps after ion impact. Ar impact creates an area depleted in benzene molecules. Some of these molecules are ejected while others are relocated away from the impact point by a pressure wave that develops in the organic overlayer
Sputtering of thin benzene overlayer physisorbed at Ag{111} surface by C60
C60 just before the impact at multilayer benzene deposited on Ag{111}
Crater formed by 20 keV C60 impact at multilayer benzene deposited on Ag{111}
Atoms are colored according to the depth of their final location. The scale goes from red (topmost) to blue.
Lateral damage generated in organic multilayer by 15 keV C60 impact
C60 impact creates a large area depleted in benzene molecules. Some of these molecules are ejected while others are relocated away from the impact point by a pressure wave that develops in the organic overlayer.
Sputtering of thick benzene crystal by 500 eV C60 projectile
Snapshots from simulations were made by gOpenMol and PovRay.
