Semiconductor package

A semiconductor package comprising:

• a first substrate including silicon;
• a first insulating layer in contact with the first substrate on the first substrate, the first insulating layer including silicon oxide, the first insulating layer having a first concentration of silicon;
• a second insulating layer in contact with the first insulating layer on the first insulating layer, the second insulating layer including silicon oxide, the second insulating layer having a second concentration of silicon, the second concentration lower than the first concentration;
• a third insulating layer in contact with the second insulating layer on the second insulating layer, the third insulating layer including silicon oxide, the third insulating layer having a third concentration of silicon, the third concentration higher than the second concentration;
• and
• a structure disposed on the third insulating layer,
• wherein the first concentration is a ratio of a weight of silicon included in the first insulating layer to a total weight of the first insulating layer,
• wherein the second concentration is a ratio of a weight of silicon included in the second insulating layer to a total weight of the second insulating layer, and
• wherein the third concentration is a ratio of a weight of silicon included in the third insulating layer to a total weight of the third insulating layer.

A semiconductor package comprising:

• a first substrate including silicon;
• a first insulating layer in contact with the first substrate on the first substrate, the first insulating layer including silicon oxide, the first insulating layer having a first concentration of silicon;
• a second insulating layer in contact with the first insulating layer on the first insulating layer, the second insulating layer including silicon oxide, the second insulating layer having a second concentration of silicon, the second concentration lower than the first concentration;
• a third insulating layer in contact with the second insulating layer on the second insulating layer, the third insulating layer including silicon oxide, the third insulating layer having a third concentration of silicon, the third concentration higher than the second concentration;
• and
• a second substrate in contact with the third insulating layer on the third insulating layer, the second substrate including silicon,
• wherein the first concentration is a ratio of a weight of silicon included in the first insulating layer to a total weight of the first insulating layer,
• wherein the second concentration is a ratio of a weight of silicon included in the second insulating layer to a total weight of the second insulating layer,
• wherein the third concentration is a ratio of a weight of silicon included in the third insulating layer to a total weight of the third insulating layer,
• wherein a thickness of the second insulating layer is smaller than each of a thickness of the first insulating layer and a thickness of the third insulating layer,
• wherein each of the first concentration and the third concentration is in a range from 20 wt % to 50 wt %, and
• wherein the second concentration is in a range from 5 wt % to 20 wt %.