Method for depositing dielectric layers

Claim 1

A method comprising the steps of: a) providing a substrate within a vacuum chamber, the substrate having a surface and, formed on the surface, a metallization pattern at least a portion of which has an aspect ratio of 1.0 or more; b) providing a mixture of gases which can react in a plasma to form silicon dioxide for deposit; c) flowing the gas mixture over the substrate such that, in the absence of an applied RF field, the gas mixture is not substantially ionized; and d) applying an RF field to the substrate such that the gas mixture forms a plasma from which silicon dioxide is deposited on at least a portion of the metallization pattern, the silicon dioxide forming a film; characterized in that e) the gas mixture comprises oxygen, argon, and at least one organosilicon compound selected from the group consisting of TEOS and TMCTS; f) during the depositing step, the temperature of the substrate is at least about 325° C. but not more than about 500° C.; g) during the depositing step, the pressure in the vacuum chamber is at least about 100 mTorr but not more than about 500 mTorr; h) during the depositing step, the power density of the RF field is at least about 0.33 W/cm 2 but not more than about 1.64 W/cm 2 , and the power level of the RF field is further selected such that the substrate is maintained, during the depositing step, at a negative dc bias of about -300 V to about -500 V; i) during the depositing step, oxygen is provided at a flow rate in the range from about 95 SCCM to about 175 SCCM; and j) during the depositing step, the dc bias and the composition of the gas mixture are further selected such that sputtering, if present, is characterized by a total sputtering rate that is no more than about 0.1 times the net deposition rate, resulting in the formation of a silicon dioxide film substantially free of soft spots and/or key holes at a deposition rate of at least about 200 Å/minute.

Claim 2

A method comprising the steps of: a) providing a substrate within a vacuum chamber, the substrate having a surface and, formed on the surface, a metallization pattern at least a portion of which has an aspect ratio of 1.0 or more; b) providing a mixture of gases which can react in a plasma to form silicon dioxide for deposit; c) flowing the gas mixture over the substrate such that, in the absence of an applied RF field, the gas mixture is not substantially ionized; and d) applying an RF field to the substrate such that the gas mixture forms a plasma from which silicon dioxide is deposited on at least a portion of the metallization pattern, the silicon dioxide forming a film; characterized in that e) the gas mixture comprises oxygen, argon, and at least one organosilicon compound selected from the group consisting of TEOS and TMCTS; f) during the depositing step, the temperature of the substrate is at least about 325° C. but not more than about 500° C.; g) during the depositing step, the pressure in the vacuum chamber is at least about 100 mTorr but not more than about 500 mTorr; h) during the depositing step, the power density of the RF field is at least about 0.33 W/cm 2 but not more than about 1.64 W/cm 2 , and the power level of the RF field is further selected such that the substrate is maintained, during the depositing step, at a negative dc bias of about -300 V to about -500 V; i) during the depositing step, oxygen is provided at a flow rate in the range from about 95 SCCM to about 175 SCCM; and j) during the depositing step, the dc bias and the composition of the gas mixture are further selected such that sputtering, if present, is characterized by a total sputtering rate that is no more than about 0.1 times the net deposition rate, resulting in the formation of a silicon dioxide film substantially free of soft spots and/or key holes at a deposition rate of at least about 200 Å/minute.