Abstract: A method of fabricating a contact structure includes the following steps. An opening is formed in a dielectric layer. A conductive material layer is formed within the opening and on the dielectric layer, wherein the conductive material layer includes a bottom section having a first thickness and a top section having a second thickness, the second thickness is greater than the first thickness. A first treatment is performed on the conductive material layer to form a first oxide layer on the bottom section and on the top section of the conductive material layer. A second treatment is performed to remove at least portions of the first oxide layer and at least portions of the conductive material layer, wherein after performing the second treatment, the bottom section and the top section of the conductive material layer have substantially equal thickness.

Abstract: A light-emitting device, including: a semiconductor stack generating a first light; and a filter formed on the semiconductor stack, including a first surface facing the semiconductor stack and a second surface opposite to the first surface; and a transparent conductive layer formed on the semiconductor stack; wherein: the filter includes a plurality of first dielectric layers with a first refractive index and a plurality of second dielectric layers with a second refractive index alternately stacked, a portion of the first light is transmitted by the filter and extracted from the second surface, the light-emitting device has a beam angle in a range of 50 degrees to 110 degrees, and the filter comprises a light transmittance of more than 90% with respect to light incident at an incident angle in a range less than 10 degrees.

Abstract: A light-emitting device, including: a semiconductor stack generating a first light; and a filter formed on the stack, including a first surface facing the stack and a second surface opposite to the first surface. The filter includes pairs of layers with different refractive indexes alternately stacked, and a portion of the first light is transmitted by the filter. The light emitting device emits a second light including the portion of the first light, and the second light includes a first directional part with a first FWHM and a second directional part with a second FWHM. The first directional part has a first angle with a normal direction of the second surface in a range of 45-90 degrees, the second directional part has a second angle with the normal direction of the second surface in a range of 0-30 degrees, and the second FWHM is smaller than the first FWHM.