Method for manufacturing a semiconductor light-emitting device and semiconductor light-emitting device

Abstract

A semiconductor light-emitting device and method for manufacturing the semiconductor light-emitting device includes a mask layer etching process on first and second mask layers provided on a Group-III nitride-based compound semiconductor substrate, the mask layer with a higher etching rate being closer to the p-type semiconductor layer; a semiconductor layer etching process; a side-etching process that selectively etches the side of the mask layer with the high etching rate to define a groove portion with a portion of the p-type semiconductor layer exposed; a ZrO 2 film forming process that forms a ZrO 2 film so as to cover the exposed p-type semiconductor layer; an Al 2 O 3 film forming process that forms an Al 2 O 3 film so as to cover the ZrO 2 film; a mask layer removing process; and an electrode layer forming process. The method for manufacturing the semiconductor light-emitting device increases the yield of lift-off with respect to the p-type semiconductor layer and can produce a semiconductor light-emitting device with an improved voltage resistance.

1 . A method for manufacturing a semiconductor light-emitting device, comprising:
 providing a Group-III nitride-based compound semiconductor including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer arranged in sequence on a substrate, and expressed as Al x Ga y In 1-x-y N (where, 0≦x≦1; 0≦y≦1; 0≦x+y≦1);   providing first and second mask layers on the p-type semiconductor layer, the first mask layer being closer to the p-type semiconductor layer and having a higher etching rate than the second mask layer;   etching the mask layers using a resist pattern on the first and second mask layers and peeling the resist pattern from the first and second mask layers;   etching the p-type semiconductor layer using the first and second mask layers as a resist pattern;   selectively side-etching a side of the first mask layer after the step of etching the p-type semiconductor layer to define a groove portion including exposing a portion of the p-type semiconductor layer;   forming a ZrO 2  film to cover the p-type semiconductor layer exposed in the groove portion;   forming an Al 2 O 3  film to cover the ZrO 2  film;   removing the first and second mask layers from the p-type semiconductor layer after the Al 2 O 3  film forming process; and   forming an electrode layer to cover an entire surface of the p-type semiconductor layer exposed by the mask layer removing process.   
     
     
         2 . The method for manufacturing a semiconductor light-emitting device according to  claim 1 , wherein an etching rate ratio of the first mask layer to the second mask layer is 5 or more. 
     
     
         3 . The method for manufacturing a semiconductor light-emitting device according to  claim 1 , further comprising the steps of:
 forming the first mask layer as an oxide or nitride by spin-coating, heat-hardening, ultraviolet-curing after spin-coating, or laser ablation; and   forming the second mask layer as an oxide or nitride by sputtering or plasma enhanced chemical vapor deposition.   
     
     
         4 . The method for manufacturing a semiconductor light-emitting device according to  claim 1 , wherein a thickness of the first mask layer is about 10 nm to about 500 nm. 
     
     
         5 . A semiconductor light-emitting device comprising:
 a Group-III nitride-based compound semiconductor expressed by Al x Ga y In 1-x-y N (where, 0≦x≦1; 0≦y≦1; 0≦x+y≦1) and including a substrate, an n-type semiconductor layer arranged on the substrate, an active layer arranged on the n-type semiconductor layer, and a p-type semiconductor layer arranged on the active layer;   a mesa portion protruding above the active layer;   a ZrO 2  film arranged to cover the mesa portion from an inner side along an edge of a top surface to a side surface of the mesa portion so as to expose the top surface of the mesa portion;   an Al 2 O 3  film arranged to cover the ZrO 2  film so as to expose the top surface of the mesa portion; and   an electrode layer arranged to cover the mesa portion from above the ZrO 2  film and the Al 2 O 3  film and electrically connected to the p-type semiconductor layer.   
     
     
         6 . The semiconductor light-emitting device according to  claim 5 , wherein the inner side wall surface along the edge of the top surface of the mesa portion of the ZrO 2  film and the Al 2 O 3  film is angled to towards the top surface of the mesa portion. 
     
     
         7 . The semiconductor light-emitting device according to  claim 5 , wherein the wall surface includes a two-step tiered structure. 
     
     
         8 . The semiconductor light-emitting device according to  claim 5 , wherein a width from the edge of the top surface of the mesa portion where the ZrO 2  film and the Al 2 O 3  film come in contact with the top surface of the mesa portion is from about 0 to about 0.5 μm.