Improved Switching Characteristics of Fast Power MOSFETs Applying Solder Bump Technology

Table 1

Typical examples of alternative packaging technologies substituting wire bonding technology.

	Embedded power technology [1]	Planar power polymer packaging technology [2]	Flip-chip-on-flex technology [3, 4]	DBC sandwich technology [5]
Interconnect technology	Sputtering + electroplating	Sputtering + electroplating	Solder bump	Solder bump
Bottom substrate	DBC	DBC	DBC	DBC
Top substrate/chip carrier	Die embedded in a ceramic $({\text{Al}}_2\hspace{0.17em}{\text{O}}_3)$ + dielectric coating (125 $\mu$m).	Die mounted on a polymer film (50 $\mu$m) applying an adhesive.	Die soldered to a flexible polymer (50 $\mu$m).	Die soldered to a 2nd DBC.
Top Cu metallization thickness	125 $\mu$m–150 $\mu$m	75–125 $\mu$m	50 $\mu$m–150 $\mu$m	typical 300 $\mu$m Cu
Interconnects:
- Diameter $d$	Vias with $d$ = 1000 $\mu$m	Vias with $d$ = 500–1000 $\mu$m	Solder bumps with $d$ = 750–900 $\mu$m	Solder bumps with $d$ = 200 $\mu$m
- Height	125 $\mu$m	$\approx$ 50–100 $\mu$m	$\approx$ 500–1200 $\mu$m	125 $\mu$m
- Pitch	not defined / [1]: 6 vias	not defined	1 bump per Al-pad	360 $\mu$m