MOSFET vs. bipolar in integrated circuits: What is the principal advantage of using MOS technology over bipolar circuitry for large ICs?

Introduction / Context:
Choosing a device technology affects density, power, and cost. MOSFET-based integrated circuits, especially CMOS, enable extremely high transistor counts with low static power, making them ideal for large-scale and very-large-scale integration (LSI/VLSI). Historically, this has been the decisive advantage over bipolar logic families for large chips.

Given Data / Assumptions:

• We are comparing mainstream advantages in IC manufacturing.
• “Complexity” here means achievable transistor count per chip (density).
• Bipolar circuits tend to consume more static power and scale poorly in density.

Concept / Approach:
MOS processes permit tiny, low-leakage transistors and complementary logic (CMOS) with near-zero static power, enabling dense logic with acceptable thermal profiles. Consequently, designers can implement much greater functional complexity on a single die at better cost per function than with bipolar processes for large designs.

Step-by-Step Solution:
Identify the core differentiator: density and static power.Relate density to achievable complexity and cost per function.Conclude that MOS's advantage is supporting much greater complexity → better economy.

Verification / Alternative check:
The universal adoption of CMOS for microprocessors, SoCs, and memory underscores MOS's density/cost advantages, even though bipolar (e.g., ECL) may offer higher raw speed in niche cases.

Why Other Options Are Wrong:
Higher operating speed (b) is generally a bipolar advantage, not MOS's. Fewer supply connections (c) is not the fundamental driver. Familiarity (d) is not a technology advantage. (e) restates the density/power idea but the keyed correct choice in this item is the complexity/economy phrasing.

Common Pitfalls:
Equating “faster” with “better” for all contexts; for LSI/VLSI, power and density win.

Final Answer:
much greater complexity (more components) than bipolar circuits : better economy