Aluminum diffuses readily into silicon. for transistors with shallow source-drain regions, annealing frequently causes aluminum to diffuse through the source-drain region and short to the substrate. this problem, called "junction spiking," can be combated through the use of a thin titanium-tungsten (tiw) barrier between the aluminum and silicon. how might such a barrier affect device performance? (hint: read the section on contact resistance in the device analysis lab.)

A2-m rigid tank initially contains saturated water vapor at 100 kpa. the tank is connected to a supply line through a valve. steam is flowing in the supply line at 600 kpa and 300 c. the valve is opened, and steam is allowed to enter the tank until the pressure in the tank reaches the line pressure, at which point the valve is closed. a thermometer placed in the tank indicates that the temperature at the final state is 200°c. determine (a) the mass of steam that has entered the tank (b) the amount of heat transfer.