Which chip process is good for diode GPP and OJ? — SUNMATE
Which chip process is good for diode GPP and OJ?
The quality of diode depends on chip technology. At present, there are mainly two kinds of diode chip processes used in the industry: glass passivation (GPP) and acid pickling (OJ).
The GPP process structure of the diode, its chip p-n junction is under the protection of passivated glass. Glass is made of glass powder sintered and melted at about 800 degrees, and then cooled to form a glass layer. The glass layer and the chip are fused into one body, which cannot be separated by mechanical methods.
In the OJ process structure of diode, the chip p-n junction is under the protection of glue. Apply glue to protect the junction, and then cure it at a temperature of about 200 degrees to protect the p-n junction to obtain voltage. OJ's protective glue only covers the surface of p-n junction.
Comparison of glass passivation (GPP) and pickling (OJ) characteristics
Due to the different structures of glass passivation (GPP) and acid pickling (OJ) chip processes, when an external force is generated, cold and hot shock will occur. The diode of OJ process structure will produce air leakage due to the mismatch between the protective glue and the silicon chip, resulting in a certain rate of device failure. TVs diodes with GPP process structure have high reliability and still perform well at 150 degree HTRB; The OJ process products can only withstand HTRB of about 100 degrees.