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Plasma Cleaner 1070

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Plasma Cleaner 1070 MODEL 1070 NanoClean Cleans specimens and holders immediately before insertion into an electron microscope; removes existing carbonaceous debris from the specimen and prevents contamination during imaging and analysis. • Multifunctional; simultaneously cleans specimens, specimen holders, and stubs • Inductively coupled, downstream plasma for optimal performance CLEAN LARGE OBJECTS AND GRIDS • Sputter-free; no change to elemental composition or structural characteristics In addition to traditional electron microscopy applications, many other • Accepts two electron microscopy specimen holders objects can benefit from plasma processing. Larger objects, such as pieces • Compatible with side-entry holders for all commercial scanning, transmission, of semiconductor wafers or scanning and scanning transmission electron electron microscopy (SEM), atomic force microscopes microscopy (ATM), or secondary ion mass • Accommodates large objects spectrometry (SIMS) holders can also be • Multiple gas inlets with mixing capabilities cleaned. • High frequency power with automatic For biological transmission electron matching network microscopy (TEM) applications, grids can • Simple setup with touchscreen interface be subjected to the plasma to promote • Handy for evacuating vacuum storage hydrophilic wetting. containers MODEL 1070 NanoClean Electron microscopy demands clean specimens and holders PLASMA CLEANING Clean, well prepared specimens are imperative for imaging and microanalysis in electron In a nonequilibrium, high-frequency microscopy. TEM requires that specimens be plasma, free electrons are prepared without altering their microstructure or accelerated to high velocities by composition. an oscillating electromagnetic field and collide with gas atoms, forming Modern electron microscopes with high ions and sustaining the plasma. The plasma ions impinge upon the brightness electron sources such as LaB6 filaments and field emission guns (FEG) use a surface with energies of less than 12 eV, which is below the specimen’s small electron probe with high beam current for sputtering threshold. microanalysis, yielding high-resolution images as well as enhanced analytical data. As probe size Cleaning occurs when reactive gas decreases and beam current density increases, compounds formed by the plasma specimens tend to become easily contaminated. chemically react with carbonaceous As a result, the quality of the specimen and material on the specimen and the cleanliness of both the specimen and the specimen holder. specimen holder are more important than ever. Fischione recommends a mixture Contamination typically comes from several of 25% oxygen and 75% argon to optimize cleaning (other gases sources: inadvertent touching of specimens or or mixtures can also be used). An specimen holders, electron microscope column oxygen plasma is highly effective contamination, and adhesives or solvents used in in removing organic (hydrocarbon) the preparation process. Even when great care is contamination. The reaction yields taken to clean the specimen, standard cleaning H2O, CO, and CO2, which are methods are often not completely successful. evacuated by the vacuum system. Model 1070 NanoClean for electron microscopy applications and scanning transmission electron microscopes The Fischione Model 1070 NanoClean cleans (STEMs), and can accept bulk specimens for specimens and holders immediately before they cleaning before conducting SEM or surface are inserted into an electron microscope. Plasma science analysis. cleaning both removes existing carbonaceous debris from the specimen and prevents contamination during imaging and analysis. Cleaning specimens and holders A low-energy, inductively coupled, high The NanoClean removes contamination from a frequency, downstream plasma effectively wide variety of materials prepared by a variety cleans the specimen surface without changing of techniques. The specimen holder is inserted its elemental composition or structural through a port into the plasma chamber. The port characteristics. Highly contaminated specimens contains a vacuum-sealing surface compatible can be cleaned in two minutes or less. with the specimen holder’s O-ring. The NanoClean readily accepts one or two side- The chamber is configured to accept one or two entry specimen holders for all commercial TEMs specimen holder ports. Ports are available for side E.A. FISCHIONE INSTRUMENTS, INC. 3 MODEL 1070 NanoClean entry specimen holders for electron microscopes manufactured by: • FEI Company/Philips Electron Optics • Hitachi High Technologies America Inc. • JEOL Ltd. • Carl Zeiss Microscopy Ports are easily interchangeable without tools in as little as 10 seconds. For cleaning specimens containing significant amounts of carbon or specimens mounted onto carbon support grids, shielded specimen holder Typical TEM specimen holder port ports are available that optimize the cleaning rate of the plasma. Imaging with confidence Plasma cleaning is an essential final step in the preparation of specimens for electron microscopy. Use the NanoClean to be confident that carbonaceous contamination will not interfere with imaging or analysis, even during fine probe microanalysis for extended periods. Plasma cleaning for SEM (EDX) The benefits of plasma cleaning are not only for TEM but also for bulk specimens, which can be readily introduced through the chamber’s top port. Specimens for SEM and surface analysis can be cleaned as well as specimen holders, aperture Model 1070 NanoClean with chamber strips, tweezers, specimen clamping rings, and lid open anything else that can be placed into the plasma chamber. Plasma chamber contained in the chamber. None of the instrument’s components are located within the The plasma is created in a cylindrical chamber chamber. made of quartz and stainless steel. Sophisticated gas dynamics ensure that the plasma is Receptacles on the front surface of the chamber evenly distributed within the chamber to can accept two ports for standard electron clean the specimen with negligible heating. A microscopy specimen holders. A view port high-frequency antenna, located outside the provides the ability to observe the inside of the chamber, inductively couples the oscillating chamber. A lid on top of the chamber allows electromagnetic power to the process gas larger objects to be placed into the plasma. E.A. FISCHIONE INSTRUMENTS, INC. 4 MODEL 1070 NanoClean Vacuum system Effective shielding prevents high frequency interference and fully complies with FCC An oil-free vacuum system is essential to prevent guidelines. contamination. The vacuum system for the NanoClean consists of a turbomolecular drag pump and a multistage diaphragm pump, an Process gas ideal combination for establishing suitable vacuum characteristics to activate and sustain the The NanoClean contains three mass flow plasma. The vacuum level is measured by a Pirani controllers and is designed to accept multiple gauge. gases. Typically, the time-proven gas mixture of 25% oxygen and 75% argon is connected to The chamber includes a load lock for rapid one of the gas inlets. The NanoClean is fitted specimen exchange which allows plasma cleaning with two additional gas inlets which accept to begin almost immediately after a specimen is gas supplies that can be blended using the inserted. An electronically actuated gate valve NanoClean’s internal mass flow technology. isolates the plasma chamber from the vacuum system. Pump down time for the chamber is less than 50 seconds. Also, the chamber can be vented Instrument controls within 5 seconds after the conclusion of plasma An easy-to-use touchscreen embedded module processing. These features make the NanoClean allows you to control individual instrument ideal for high-throughput applications. functions, such as delivered power, chamber pressure, gas mixture, and process time. The NanoClean can also be used to evacuate individual specimen holder vacuum storage For dedicated cleaning of electron microscopy containers and cyrotransfer TEM specimen specimens and holders, the NanoClean includes holder dewars. a recipe that yields optimal plasma processing conditions. All the user needs to do is insert the A port plug inserted into the specimen holder specimen holder into the specimen holder port port seals the chamber under vacuum when the and establish the process time. The instrument instrument is not in use. automatically controls the vacuum, supplies the appropriate power and gas flow, and energizes the Power supply plasma. The high frequency (13.56 MHz) oscillating Recipes are stored for applications such as power supply is used to initiate and sustain a enhancing the hydrophilic properties of biological low-energy, inductively coupled plasma (ICP). support grids. Custom recipes to set up a unique An ICP is ideal for microscopy applications since set of operating conditions can be created and it delivers ions with energy low enough that the stored by using the touchscreen. specimen’s properties are not altered. The display provides a real-time representation An automatic matching network ensures that the of the instrument’s key parameters including the high frequency power is effectively coupled to remaining processing time. the plasma and the delivered power is suited for the application. The matching network regulates Cleaning terminates automatically when the plasma power for a variety of conditions, objects specified time has elapsed. A visual indicator to be processed, or gases employed. It also notifies the user that plasma cleaning is complete. guarantees plasma compatibility with specimen The specimen remains under vacuum until the holders produced for diverse electron microscopes. user initiates the venting process. E.A. FISCHIONE INSTRUMENTS, INC. 5 .
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