The present invention relates to surface-emitting type devices and methods for manufacturing the same, and burn-in methods for surface-emitting type wafers.
Surface-emitting type elements such as surface-emitting type semiconductor lasers may change their initial characteristics when a current is injected after their completion, and therefore a so-called burn-in process is performed, in which a current is injected for a predetermined period of time in a high temperature condition during the manufacturing process to stabilize the characteristics. (see Non-Patent Document 1) Also, because surface-emitting type elements emit light orthogonally to a substrate surface, they can be subjected to a burn-in process in the state of a wafer.
However, in the state of a wafer that has 1000-10000 elements, in order to perform a burn-in process for all of the elements, a current source of 10 A-100 A is required, assuming that a drive current for each of the elements is 10 mA. Furthermore, in order to circulate a current in series in each of the elements, probes are required in a number that equals to at least the number of the elements or greater. Accordingly, there is a problem in that not only the burn-in process is time-consuming, but also the cost increases.
[Non-patent Document 1] Service Life Test Technology, Colona Publishing Co., 1986, page 176-183, by Kenji Kitagawa