After improving the assembly system, the remaining automotive diodes f
ailures, above 4% in operation, was associated to the internal strain,
based on the RVT test results. The X-ray diffraction spectra the rock
ing curves - allowed the pointing out of the internal strain induced b
y the grinding and diffusion processes. New conditions for the diffusi
on process, which reduce the induced strain on the B-AI diffused side,
were established. An important improvement of the automotive diodes r
eliability was obtained, the failure percentages diminishing by a fact
or between 4 and 8, in operation and in RVT tests. (C) 1998 Elsevier S
cience Ltd. All rights reserved.