Solver's Productivity

• the first generation includes the scanning tunneling microscopes (STM). They were invented in 1981;
  
• liquid, air, vacuum and high vacuum versions of these devices have been made to be widely used in practice;
  
• atomic force microscopes were invented in 1986. In combination with the STM this is the second generation of probe microscopes;
  
• since 1993 there has been developed a new generation of devices using the multimode principle in their operation.
  The use of modulation and resonance techniques (forced or resonance probe oscillation with the oscillation amplitude and phase registration in the course of scanning) so called noncontact (the force acting on sample up to 10^-13N), semicontact or tepping (the force acting on sample from 10^-11 to 10^-9N) and force modulation modes to investigate the hardness and viscosity distribution in the surface layers, tunneling spectroscoping modes; close field optical modes including the photo-; electron-, electric-, chemical- luminescence including the low temperature one, surface plasmons registration etc, lateral force registration mode, "lift" modes (modes to register magnetic electric fields of force, optical signals - they are effected by means of a repeated scanning over a known relief at a given distance above the surface), "capacity" modes and the surface potential space change registration mode, thermal modes - surface local temperature change registration in case of unbalanced action on the sample), microprobe Auger mode (not yet implemented), microprobe SIMS modes (first informations already available) and various on-sample action modes (by electrical impulses, ions, clusters, electrons injection, magnetic impulses with a possibility for super high density magnetic recording, tensoactions; at the same time it is possible to change in a controlled way the absorption layer initiating chemical reactions). The multimode development has transformed the probe microscope into a powerful analytical and preparation tool to model processes and investigate surface properties; this third generation devices are being developed and they are currently working up the market. It should be noted that the third generation devices development is not yet over and there are no devices on the market yet that would be provided with all the above mentioned functions, especially having the capability to carry out investigations in the multimode within a wide temperature range in ultrahigh vacuum;
  
• as the second stage in the devices development one can consider the appearance of new ideas to implement their multiprobe versions. These units while having all the capabilities of the third generation devices makes it possible to investigate both the electrical properties of the modelled nanoelements and to use different function probes (for example, magnetic probe, cluster injection probe - gold covered, for instance; current/force probe). The development of this devices' generation is closely connected both to the development of probes manufacture technologies and techniques to access individual probes and read their state.
  
• NT-MDT as well as some other companies (Digital Instruments, Topometrics, Park Scientific Instruments, Zeiss, etc (see Scanning Probe Microscopy Web page).) is currently developing and producing the third generation scanning probe microscopes and probes for them (cantilevers, close field optical microscopy probes). It is also engaged in the fourth generation instruments development.
  

Solver-P4's capabilities

The Solver-P4 belongs to the third generation scanning probe microscopes. The device is designed for topographical investigations of surfaces physical properties and modification in various objects in air and liquid mediums. Viewing modes: atomic force microscopy mode, scanning tunneling mode, resonance mode, atomic force microscopy modulation mode. The modulation modes allow the oscillation amplitude and phase registration. In the a.m. modes it is possible to investigate the same surface area. The device is provided with a close field optical microscopy head equipped with a feedback loop to support the beamguide oscillation amplitude (Shear Force microscope).
The Solver-P4 can be equipped with four types of measuring heads and three types of scanners with scanning fields of 7x7x1.5 mm³, 16x16x2.5mm³, 50x50x4mm³. The measuring heads are installed on the scanner where a sample is also secured (the sample dimensions are up to 40 mm in diameter and 10 mm in width) and connected by means of a multipins jack to the instrument's electronic modules.
The instrument's scanners are provided with a coarse sample approach system (implemented using a stepping motor) that allows, after the sample and probe approach/withdrawal, for returning to the same position with an accuracy to nanometers. This enables the same surface area investigations lasting many days (study of slow processes, initiated agitation degradation processes...).

SF002 SFM/LFM head with 4 quadrant detector to provide lateral force measurements and with resonant SFM system
This is the basic head of the Solver-P4 multimode scanning probe microscope. The head contains an optical positioning system for the cantilever position registration including a 1 MW semiconductor laser having 670 nm wave length, a 4-sectional photodiode, probes securing and positioning systems and preamplifiers. Cantilevers are fixed in a special holder and placed on a table positionable by means of two microscrews. The Solver-P4 allows for using four types of tables:

• the force table (FT-1) to measure in contact and contact modulation modes;
  
• an STM/AFM table containing an STM preamplifier. The use of this table allows to register in addition to the FT-1 in case of a conducting cantilever application the current in the system 'cantilever's tip - substrate and to work in the tunneling microscope mode;
  
• the resonance microscopy table (RMT), making it possible, in addition to the possibilities provided by the FT-1, to work in the resonance microscopy and noncontact modes. This table contains a piezovibrator to actuate the cantilever's oscillation;
  
• the universal multimode table combining the capabilities of the three previously mentioned tables.

ST002 STM head with precise preamplifier (3pA-1nA)
The use of this head makes it possible to work in the tunneling microscopy, tunneling spectroscopy modes, to carry out electrically induced surface modification. The head contains a precision preamplifier allowing operation at low currents. This preamplifier noise is under 1.5 peak amperes in the frequency range of 5.5 kHz.

ST001STM head with preamplifier (10pA-10nA)
The use of this head makes it possible to work in the tunneling microscopy, tunneling spectroscopy modes, to carry out electrically induced surface modification. The operation range - 10 pA - 10 nA. This preamplifier noise is about 5 pA in the frequency range of 12 kHz.