Patent ID: 6271137
Filing Date: 2001-08-07
Classification: C23C,H01L

Abstract:
A method of forming interlevel aluminum contacts in integrated circuits, comprising the steps of:forming a first insulating layer over a conducting layer;forming a first contact opening through the insulating layer to expose a portion of the conducting layer;forming a first barrier layer over the insulating layer, in the opening and over the exposed portion of the conducting layer;beginning to deposit aluminum at a temperature below approximately 350.degree. C. on the barrier layer at a relatively low rate of deposition;during said beginning to deposit aluminum step, beginning to raise the temperature of the integrated circuit;continuing to deposit aluminum while increasing the temperature from below approximately 350.degree. C. to a desired temperature between approximately 400.degree. C. and approximately 500.degree. C.;after the integrated circuit temperature has reached the desired temperature, depositing an aluminum layer on the integrated circuit to a desired thickness;during the desired thickness depositing step, controlling the rate at which the aluminum layer is deposited to allow deposited aluminum to migrate into the opening so as to provide a substantially complete contact fills;patterning the aluminum layer to define a first aluminum interconnect layer;forming a second insulating layer disposed over the first aluminum interconnect layer and the first insulating layer;forming a second contact opening in the second insulating layer, wherein the second contact opening exposes a portion of the first aluminum interconnect layer directly over the first contact opening;forming a second barrier layer over the second insulating layer and in the second contact opening;beginning to deposit a second aluminum layer at a temperature below approximately 350.degree. C. on the second barrier layer at a relatively low rate of deposition;during said beginning to deposit a second aluminum layer step, beginning to raise the temperature of the integrated circuit;continuing to deposit the second aluminum layer while increasing the temperature from below approximately 350.degree. C. to a desired temperature between approximately 400.degree. C. and approximately 500.degree. C.;after the integrated circuit temperature has reached the desired temperature, depositing the second aluminum layer on the integrated circuit to a desired thickness; andduring the step of depositing the second aluminum layer to a desired thickness, controlling the rate at which the second aluminum layer is deposited to allow deposited aluminum to migrate into the second contact opening so as to provide a substantially complete contact fill.