Semiconductor wafer having multiple semiconductor elements and method for dicing the same

A method for dicing a semiconductor wafer, which includes a first layer having a first refraction index, a second layer having a second refraction index, a plurality of semiconductor elements disposed in the first and/or second layers, and a layer removal region, wherein the first refraction index is different from the second refraction index, and wherein the first layer and the second layer are stacked in this order, the method comprising the steps of:

• removing a part of the second layer along with a cutting line so that the layer removal region is formed, wherein a laser beam is irradiated on the first layer in the layer removal region without passing through the second layer;
• irradiating the laser beam on the first layer along with the cutting line so that a modified region is formed in the first layer;
• and
• separating a semiconductor element from the wafer by using a crack generated by the modified region.

A semiconductor wafer comprising:

• a first layer having a first refraction index;
• a second layer having a second refraction index, which is different from the first refraction index;
• a top layer;
• a plurality of semiconductor elements disposed in the first layer, the second layer, and/or the top layer;
• and
• a layer removal region, wherein
• the first layer, the second layer and the top layer are stacked in this order,
• the semiconductor elements are capable of being separated each other by irradiating a laser beam on the first layer along with a cutting line,
• the laser beam irradiation on the first layer provides a modified region in the first layer along with the cutting line so that the semiconductor elements are capable of being separated by a crack generated in the modified region,
• the layer removal region is provided in such a manner that the top layer in the layer removal region is removed from the wafer in order to irradiate the laser beam on the first layer in the layer removal region without passing through the top layer.