Chapter 4, Problem 4.34P

Consider the thin integrated circuit (chip) of Problem3.150. Instead of attaching the heat sink to the chipsurface, an engineer suggests that sufficient coolingmight be achieved by mounting the top of the chiponto a large copper $\left(k=400\text{W/m}\cdot \text{K}\right)$ surface that islocated nearby. The metallurgical joint between thechip and the substrate provides a contact resistance of $R_{t,c}^{"}=5\times {10}^{-6}{\text{m}}^{\text{2}}\cdot \text{K/W,}$ and the maximum allowablechip temperature is $\text{85°C}\text{.}$ If the large substrate temperatureis $T_2=25°\text{C}$ at locations far from the chip, whatis the maximum allowable chip power dissipation $q_c?$