Slide 37 of 64
This is a slightly different plot of the same information on the previous slide. As the area of the emitter drops the speed mostly stays the same until the emitter width is comparable to the base thickness, but the power (V x Ic) drops linearly with this area. Hence the power is dropping with the square of the design rule (for the emitter anyway). Notice the AREA parameter does not sense the different ways that the emitter can shrink.