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New rapid reliability tests were introduced for monitoring, on reliability criteria, the technological processes for power diodes manufacturing. SEM, EDAX, AFM and SIMS analyses were used for the optimization of double diffusion and multi-layer metal deposition processes. New control methods and statistical graphs were introduced for monitoring the new technological conditions. Higher yields, for higher electrical and reliability performances, were obtained. The project was performed in the frame of CALIST national R and D program.

The paper presents a method for the improvement of product reliability based on screening at the wafer fabrication stage, which is time and money saving for manufacturer. It relates to the manufacture of automotive rectifier diodes in DO21 case. The aim was to establish a mechanical screening procedure based on the correlation between the resistance to applied pressure of glass passivated chips and the results of standard reliability RTV test (rapid thermal variations).

The paper presents a method for the estimation of product reliability based on tests performed at the chip fabrication stage, which is time and money saving for manufacturer. It relates to the manufacture of automotive rectifier diodes in DO21 case. The aim was to establish to a correlation between the pressure resistance of chips and the results of standard reliability test, RTV (rapid thermal variations).

A low cost and reliable glass passivated structure for 35 Arms thyristors has been manufactured using sealed tube diffusions, mesa etching from both sides of the wafer and a lift-off metallisation technique. Best trade-off I/sub G_T_/d/spl nu//dt performance has been designed using two dimensional simulation of triggering mechanisms, followed by experimental validation of calculated values.

An optimization of the double diffusion process performed with B-Al and P paint-on sources is presented. An increase of the yield by 25-35% for the fabrication of the power rectifier diodes having V/sub BR/spl ges//1200V is obtained. The work was carried out within the frame of CALIST National Program.

The authors developed a computer modeling program which solves the one-dimensional heat flow problem for a sequence of layers of material; dissipated power waveform is input in the form of an analytical function of time and junction temperature; heat flow at the borders may be given as constant temperature or zero gradient (or any combination thereof). The program was used to simulating as closely as possible medium power automotive suppresser diodes currently produced in Baneasa, under real pulse-test conditions. Predicted temperatures have been found to agree with experimental findings, and suggest as a possible failure trigger mechanism the melting of the solder a the pellet-substrate interface.

A building-in reliability technology was implemented to the manufacturing of Schottky power diodes. The main input variables (process and control parameters) contributing to the reliability were identified, optimised and monitored in the purpose to increase the reliability level.

Statistical analyses were used to build an efficient reliability monitor for power semiconductor devices. Benefits for the device manufacturing are obtained.