Say whether these statements are TRUE or FALSE. 1. Atlantis is the name of the U.S

1. Atlantis is the name of the U.S. marine exploration program. 2. The shuttle’s mission lasted for a fortnight. 3. There were four astronauts on board the spacecraft. 4. The crew brought back an ammonia pump that recently had failed on the station. 5. Nowadays the level of scientific understanding among Americans is very high. 6. The progress in medical science will slow down because of the loss of the program. 7. The Space Shuttle program has brought many problems that deeply impacted everyday lives of common Americans.

2. Give synonyms to the following words from the text:

exploration, to carry out, a shuttle, construction, spare, to eliminate, community, to include, miniature, environment, composite, to grow.

7. IBM Cooks Up Super-Thin Graphene Chips

a circuit	схема	excess	надлишок
a wafer	тонка кристалічна пластина	a field-effect transistor	польовий транзистор
to grapple	боротися	complementary	додатковий
honeycomb	стільники	yield	виробіток, вихід
a flake	пластинка	elastic	гнучкий
a challenge	проблема, виклик	impermeable	непроникний
top-gate	верхній закрив	alumin(i)um	алюміній

Scientists at IBM have figured out a way to use graphene in the production of circuits. Graphene is an incredibly thin substance; in fact, it’s only a single atom thick. IBM researchers have demonstrated a graphene circuit which integrates all circuit components onto a single wafer made of silicon carbide. Integrating it monolithically – meaning in one unit – with other materials is a problem researchers have been grappling with since 2004, when the material’s properties were first demonstrated.

What Is Graphene?

Graphene is essentially carbon that comes in sheets one atom thick densely bonded together in a honeycomb crystal lattice. You can think of graphene as a plane of graphite – that stuff making up your pencil lead – which is one atom thick. In 2004, physicists at the University of Manchester and the Institute for Micro-electronics Technology in Chernogolovka, Russia, first isolated individual graphene flakes and measured their electronic properties.

About IBM’s Announcement

The integrated graphene circuit announced by the IBM researchers operates as a broadband radio frequency mixer at frequencies up to 10 GHz. Frequency mixers are used in all communications devices – radios, TVs, cellphones and radio satellites. The circuit announced by IBM is an analog circuit. It’s designed to work – meaning switch on and off – at 10 GHz, which is 10 billion times a second. IBM is working to improve on that.

Creating graphene circuits is difficult because combining graphene with other materials has slowed down the circuits. Wafer-scale fabrication of graphene has been one of the biggest challenges in realizing the promise of graphene electronics. To make the integrated graphene circuit, the IBM team first heated a silicon carbide wafer to release silicon and form a layer of graphene on its surface. The graphene film was allowed to grow to two or three layers in thickness, and then the silicon surface was heated to 1,400 degrees Celsius. Top-gated dual-fingered field-effect transistors were then integrated with aluminum inductors. Following this, the wafer was spin-coated with a thin polymer, and a layer of hydrogen silsesquioxane was applied to create active channels. The active channels were then carved by e-beam lithography, the excess graphene was removed with an oxygen plasma laser, and the circuit was cleaned with acetone. IBM’s circuit measures one square millimeter.

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