Chemical vapor deposition of titanium
View Patent ↗A titanium layer is formed on a substrate with chemical vapor deposition (CVD). First, a seed layer is formed on the substrate by combining a first precursor with a reducing agent by CVD. Then, the titanium layer is formed on the substrate by combining a second precursor with the seed layer by CVD. The titanium layer is used to form contacts to active areas of substrate and for the formation of interlevel vias.
1. A memory device, comprising: a memory array; a control circuit operatively coupled to the memory array; and an input/output circuit operatively coupled to the memory array, wherein at least one of the memory array, the control circuit, or the input/output circuit further comprises a via having:
a layer of a titanium alloy formed to overlay walls of a contact hole, wherein the titanium alloy comprises titanium and an element selected from the group consisting of zinc, cadmium, mercury, aluminum, gallium, indium, tin, silicon, germanium, lead, arsenic and antimony,
a titanium silicide contact formed in the layer of titanium alloy and having a composition that is different than the layer of titanium alloy, the titanium silicide contact being directly coupled to the layer of titanium alloy, and a fill coupled to the layer of titanium alloy, the fill comprising a metal selected from the group consisting of tungsten and aluminum.
2. The memory of claim 1 , wherein the titanium has an atomic percentage of from about 50% to about 90% of the titanium alloy.
3. The memory of claim 1 , wherein the fill has a level approximately equal to a height of the via.
4. A memory device, comprising: a memory array; a control circuit operatively coupled to the memory array; and an input/output circuit operatively coupled to the memory array, wherein at least one of the memory array, the control circuit, or the input/output circuit comprises:
a layer of a titanium alloy formed to overlay walls of a contact hole, wherein the titanium alloy comprises titanium and an element selected from the group consisting of zinc, cadmium, mercury, aluminum, gallium, indium, tin, silicon, germanium, lead, arsenic and antimony; and
a titanium silicide contact formed in the layer of titanium alloy and having a composition that is different than the layer of titanium alloy, the titanium silicide contact being directly coupled to the layer of titanium alloy and produced using a method comprising:
forming a seed layer within the contact opening by combining a first precursor with a first reducing agent, and;
forming the titanium alloy layer within the contact opening by combining a titanium-containing precursor with the seed layer to form a titanium alloy layer having at least 100% step coverage within the contact.
5. The memory of claim 4 , wherein the titanium has an atomic percentage of from about 50% to about 90% of the titanium alloy.
6. The memory of claim 4 , further comprising:
a contact hole conductive plug formed from selective deposition of a conductive material selected from the list including tungsten and aluminum.
7. The memory of claim 6 , further comprising:
a titanium nitride layer disposed underneath the contact hole conductive plug and above the titanium silicide.