He – she He says something about you Professional life In a manufacturer Hundreds of trillion transistors Every day, when your title is “Mr. Transit.” This is what colleagues often call Taher Ghanaian, Old colleague and director of the recruitment process in Intel Technology Development Group. Ghanaian profession extends three decades in the company and resulted in more than a thousand Patent filings. He had a hand in every big change in Cmos Transistor During this time a period.
like Intel It is heading towards another major change – the step From Finfets to Ribbonfets (Memory Nanoscopic transistorsin general) –IEEE SICTRUM Ghani asked what is more dangerous so far. In an era when it is complete Structure Subordinate device It has turned, his somewhat sudden answer was a change in 2008 and who left the transistor searching – from abroad – similar to what happened before.
3 major changes to the transistor
Before presenting this year from Ribbonfets, there was Three major changes to the CMOS transistor. At the end of the century, Devices It looked like they were always, smaller than ever. It was built in a plane Silicone It is a source and sink Disputed from the canal area. Above this area is gate Mixed – a thin layer of Silicon oxide Insulation Covered with a thicker piece Multi -crystal Silicon. Voltage At the Polysilicon, it causes a connecting channel to fill the source and deplete, allowing the current flow.
But as Engineers Continue reducing this essential Heikal, the production of a device that led a sufficient current through it-especially for half of the devices that were performed positively Holes Instead of electrons – because they are more difficult. The answer was to extend the silicon Crystal Poetic, which allows the drawings speed Through faster. when Intel Declare that it Silicon tense plan in 2002This was done by adding a little Gruemanium silicone To the source and discharge, and allow the largest crystal structure of the material pressure on the silicone in the channel between them.
The thin layer of Silicon dioxide The isolation that separated the portal from the channel is now only five atoms
In 2012, and Finfet receipt. This was the biggest structural change, as it was mainly turning the device channel area on its side so that it protrudes like the fin over the surface of the silicon. This was done to provide better Control On the current flow through the channel. By this point, the distance between the source and the drainage is so reduced to the point that the current will leak even when it is supposed to be stopped. The champion structure allowed the chips makers to avoid the stream of the gate over the canal area so that it surrounds the canal area on three sides, which provides better control than level The transistor portal is monozer.
But between tense silicon and vinice came the most dangerous step in Intel, according to Ghani, a high gate of metal.
If you take the three big changes in Transistors During this contract, my personal feeling is that the K/Metal Gate was the most dangerous ever. ” IEEE range In IEEE international Electron The device meeting in December. “When we went to a high gate K/Metal, this is taking heart From the mos transistor and change it. “
As Taher and his colleagues said in Article in IEEE SICTRUM at that time“The main problem we had to overcome is that we were a few years ago, ran out of atoms.”
Preserve More Law Scaling In this era, it means reducing the smallest parts of the transistor with a 0.7 factor with each generation. But there was one part of the device that has already reached the maximum. The thin layer of silicon dioxide The isolation that separated the gate from the channel, after it was diluted for 10 times since the mid -1990s, was now only five atoms.
The loss of more materials was simply impossible, and worse in five atoms Electrical insulation portal He was barely doing his job. the insulator It is supposed to be allowed to voltage at the gate to drop electrical The field is on the channel but at the same time, continue charging from the leakage between the gate and the channel.
“We initially wanted to make one change simultaneously,” to remember Ghani, Starting Silicon dioxide replacement for something that can be thicker physically but still displayed Electrode Also completely. Something is called high performance, or High K, electric insulation. When Intel Elements research Ghani said: “They actually found it if you were doing a Policillon with High k.There is an interaction between a poly and a high K. “This reaction is effectively connecting the effort in which the transistor is turned on or turned off – the threshold voltage – worse value From if you have left well on your own.
“There was only a way out … to do a metal gate as well,” says Ghani. Minerals will be better associated with high electric insulation K, which eliminates the problem of attachment while solving some other problems along the way. But finding the appropriate metal – Minerals Really, because there are two types of transistor, Nmos And PMOS – created her own problems.
“Like a dog to a BonesThe entire organization was searched to do so. ” -Tahir Ghaani, Intel
“The problem with the metal portal is that all Material it will be [worked]… high temperatures “needed to build the rest of the device, Ghani says.
Once again, the solution had actually ignited risk Beyond that. Intel will have to take a series of steps that you used reliably to build and reverse transistors.
The basic process included building the portal of the portal Firstly Then using its dimensions as borders the company carried out in the rest of the device. But the mineral gate pile will not survive the utmost degree of this alleged gate. “The road was the opposite of flowing and doing the gate in the end,” explained by Ghani. The new process, called Gate Last, is involved in the start of a doll portal, a group of polysilicon, continuous with He treatsThen remove the doll and replace it with high electric insulation and the metal gate. Add after other complications, the new gate staple had to be deposited using an INTEL tool at all that you did not use chip production The name The atomic layer deposited. (Do what the name suggests.)
“We had to change the basic flow that we made several decades ago,” Ghani says. “We put in all these new elements and others the heart of the transistor; we started to use tools We have not done before in industry. So, if you look at a large number of challenges we faced, I think it was clear that the most challenging project I worked on. “
45 nm node
This was not the end of the story, of course.
The new process had to produce devices reliably and Circles Full ICS with degree to credibility It would ensure its economic use. “It was a big change, we had to be very careful,” Ghani says. “Thus we took our time.” Intel developed operations for both NMOS and PMOS, then built Chips From each device separately, then together before moving to more complex things.
Until then, it was not clear that the K/Metal gate would be up Make As is the next for Intel manufacturing The operation, 45 nm knots. all a job To this point it was done using design The rules-transportation and circular engineering-the current 65 nm instead of a future 45 node nm. “Every time you are He goes For a new design rules There are problems that the design rules themselves bring. “So you don’t want to confuse high K/Metal gate problems with base issues.
“I think it took almost a year and a half before we think we are ready to get the first return,” he says. exam Structures [CK].
“He was the first … a lot very goodly good for the first time,” Ghani recalls. Knowing the high extent of the initial return and looking at the amount of time that the team had before it needed to provide a 45 nm knot administration He is committed to making a high gate K/Metal, it’s the following production technology. “Like a dog to bone, the entire organization was suffering from this to do so,” he says.
When asked if he still believed that Intel is an adventurer as it was when it developed and published a high K/Metal gate, Ghani responds in the affirmative. He says, “I think we are still.” Delivery of the rear side power– Technology Save power And reinforcement performance By moving power link Under the transistors. “Seven or eight years ago, we decided to really look at the back contacts of the authority deliveryAnd we continued to pay. “
From your site articles
Related articles about the web
