High K gate metal candidates

[verndewd]

quite Honestly an alloy was what I was thinking initially,someone suggested Ru.I know osmium can be very reactive at elevated temps.From here i am drawing a blank and need to read more about the properties.Of all these metals.

 

[Varmint]

Originally posted by: ramuman
You can have a much larger range of metal work functions though. Like I said though, not sure how much that alone was a factor. Metal gates have other advantages over Poly-Si (e.g. less gate depletion).

A couple of years ago, I think the end result was that industry settled on fully silicided metals for the gate (I've seen some of Intel's IEDM papers where NiSi was the weapon of choice in this manner).

Intel didn't detail too much about the 45nm node, so I'm unsure, and they're right to protect their IP. They're basically going to be the first to implement a full high-k process in mass production, so what ever they're doing must be working.

Intel has probably solved the issues with tuning metal gate work functions.

I've not heard that IBM has given up on Fusi gates w/ high k oxides, though it's possible, especially at 45 nm. There are many ways to skin a cat.

 

[verndewd]

What I have gathered from fusi isnt really implying any use in the near future,But i expected highk to be farther off as well until Intel announced otherwise.

Its like a rollercoaster with these guys.

 

[cougar1]

AFAIK, electrically FUSI gates show a lot of promise. For example IMEC has shown some really promising data for both nmos and pmos on a few devices. However, there is a major problem in terms of manufacturability. FUSI gates are formed by depositing a layer of polysilicon and then of nickel (or another metal) and then heating to form the silicide. The problem is that the rate of silicidation is strongly dependent on the grain sizes of the polysilicon film, which tends to vary significantly across a 300mm wafer. So portions of the wafer will be adequately silicided, while other portions may not be completely silicided and other portions may be over silicided (eg. nickel diffuses through the polysilicon and into the High-K or even the channel, killing the devices). Overcoming these problems will be very difficult.

 

[verndewd]

There is a good amount of data at applied to substantiate the issues it faces.You just never know whos developing what solution.And its all hush hush.