Michael G. R. Thomson

Electron beam technology-SEM to microcolumn

As a continued effort to improve the performance of low energy scanning electron probe systems for application in microscopy, lithography, metrology, etc., miniaturized electron beam columns, approximately 3 mm in length, demonstrating a probe size of 10 nm with a beam current of >=1 nA at 1 keV, have been successfully developed. This paper presents current status, future directions and potential applications of these microcolumns.

Energy distributions of Zr/O/W Schottky electron emission

The energy distributions of electron emission from a Schottky emitter have been studied at tip temperatures from 1450 to 1800 K and angular current densities from 0.1 to 240 μA/sr. We have observed broadening of the energy distribution, with increase of angular current density and decrease of tip temperature, from 0.4 to 1.32 eV resulting from electron tunneling and electron–electron interaction. Good agreement between the experimental results and predictions from Monte Carlo simulation of the emission process is observed.

A 5GHz Duty-Cycle Correcting Clock Distribution Network for the POWER6 Microprocessor

Microprocessor global clock distribution networks use long buffered wires where reflections can be significant. Using accurate transmission-line models and optimization, these reflection effects can be exploited to improve clock-distribution characteristics. The clock distribution network of the P0WER6 microprocessor is designed to run at frequencies exceeding 5GHz using only inverters and transmission lines and is capable of on-the-fly duty-cycle correction

Electron-beam microcolumn technology and applications

A fully functional electron beam microcolumn, 3.5 mm in length, demonstrating a probe size of 10 nm and beam current >= 1 nA at 1 keV has been successfully developed. This paper presents its current status and future directions. Potential applications ranging from low cost scanning electron microscopy to arrays of such microcolumns for lithography, metrology, testing etc. will be discussed.

Optimization and modeling of resonant clocking inductors for the POWER8 TM microprocessor

A parameterized model for resonant clocking inductors embedded in a dense power grid was developed using extensive electromagnetic simulations. The resulting model was used to support resonant clock designs for the POWER8TM microprocessor. The model enabled tuning of the inductance attached to each clock sector to optimize its resonant behavior, resulting in a 33% reduction in clock power. Simulations using the model showed excellent agreement with measurement for inductance, Q and global clock power. Inductor to inductor and inductor to flip-chip solder ball interaction was minimized by shielding provided by the dense power grid.

An electron beam microcolumn for multi-beam applications

Summary form only given. Highly miniaturized electron beam columns based on a field emission source and microfabricated electron optical components have been developed. A 1 keV microcolumn operating with a miniaturized Zr/O/W Schottky emitter has been successfully evaluated for the first time. This paper will present the results obtained with the new microcolumn and discuss present efforts to further improve column performance with respect to resolution, beam current, and deflection field size.

Fully-scaled 0.25-micron bipolar technology using variable shaped electron-beam lithography

The successful application of sub-micron scaling principles to device fabrication involves an integration of tool, resist system, and process control. The precision overlay capability of a modified IBM EL-3 variable shaped beam lithography tool has been used to achieve optimized scaling of a 0.25 micrometers bipolar technology. Although the total device size is strongly coupled to linewidth control and overlay accuracy for all circuit levels, the overlay between the emitter opening and the shallow trench isolation is considered to be the most critical. We report on the integration of an advanced electron beam lithography and resist process capability with an innovative bipolar device technology to achieve emitter coupled logic (ECL) delays of 20.8 ps at a switching current of 1.1 mA. These results demonstrate the feasibility and performance leverage that can be accomplished through the aggressive scaling of conventional bipolar technologies.