Method for manufacturing silicon substrate having gettering capability
AssigneeUnited Microelectronics Corp.
InventorChen-Chung Hsu
Life of this patent
Estimating the term…
Abstract
A method for manufacturing silicon substrates having gettering capability that results in a low complexity manufacturing with a corresponding reduction in the cost of production. The first embodiment of the invention involves the use of a silicon nitride layer as a mask in the etching of the silicon substrate to form the damaged layer. The second embodiment of the invention makes use of a first pad oxide layer as a mask in the etching of the silicon substrate to form the damaged layer. Hence, a single-face etching rather than double-face etching of the silicon substrate is used in the formation of the damaged layer in this invention, so there is no need for the performance of mirror processing operations before subsequent processes.
Claims10
A method for manufacturing silicon substrates having gettering capability, which comprises the steps of:
- (a) providing a silicon substrate having a top surface and a bottom surface;
- (b) forming a first pad oxide layer over the top surface, and a second pad oxide layer over the bottom surface;
- (c) forming a silicon nitride layer only above the first paid oxide layer;
- (d) using the silicon nitride layer as a mask to remove the second pad oxide layer until the bottom surface of the silicon substrate is at least partially exposed;
- and
- (e) using the silicon nitride layer as a mask, etching the bottom surface of the silicon substrate for about 1-3 minutes using a solvent composed of potassium hydroxide and deionized water in a molar ratio of 1 to 6 so that the silicon substrate has the gettering capability, wherein the etched bottom surface forms a damaged layer having a thickness of about 75-95 .ANG..
A method for manufacturing silicon substrates having gettering capability, which comprises the steps of:
- (a) providing a silicon substrate having a top surface and a bottom surface;
- (b) forming a first pad oxide layer over the top surface, and a second pad oxide layer over the bottom surface;
- (c) using the first pad oxide layer as a mask to remove the second pad oxide layer;
- (d) etching the bottom surface of the silicon substrate for about 1-3 minutes using a solvent composed of potassium hydroxide and deionized water in a molar ratio of 1 to 6 to form a damaged layer so that the silicon substrate has the gettering capability, the damaged layer having a thickness of about 75-95 .ANG.;
- and
- (e) forming a silicon nitride layer only over the first pad oxide layer.
Dependencies are inferred from the claim text.