Scientific American on 3-D Chips

m5shiv writes: "Scientific American is running a feature on 3-D Memory Chips. These devices look like they will significantly reduce the cost of PDA's and other handheld devices as well as replacing analog film. By stacking devices vertically, density goes up considerably. The company, Matrix Semiconductor, appears to have some very interesting investors such as Kodak, Sony and Microsoft."

Comments

3D

[Anonymous Coward]

First 3D-Glasses
Next 3D games.
Then Doritos 3D
Now 3D-Memory Chips
What's the next?

Re:Eggs in many baskets

[bdoliver]

No its called venture capital. Anytime you are making money, there becomes a need to spend it. This is a good way for big companies to spend all that cash they are generating. It does look good that they are stimulating new startups, however I am quite sure they expect a return on their investment.

The most interesting thing...

[Evil Oli]

about the article in my opinion was the part saying that we are nearing the limit of miniaturisation of electronic components.

I mean, think about it.

If we're going to reach the limit of how small we can make these transistors by say 2020 (by which time we'll most likely be up to around 30Ghz processors), that's a major limitation in this industry.

The way I see it, it could go one of two ways:
1. We reach an inescapable limit of electronics, and the entire computer semiconductor industry implodes because it can't keep up with it's own reputation for performance increases.

2. Before that deadline occurs, some new fantastic and mindblowing technology is created. By this I don't mean some 'chip-stacking-bastardisation' of electronics but some true breakthrough.

Whichever way it goes, it's going to be very exciting, and I'm glad I'll be around to see it. Considering how much our lives are impacted by electronics these days, it could be the modern-day equivalent of the industrial revolution.

Interesting morning read...

[omega9]

For sure, this was a relaxing read while sitting at my desk this morning. But as it went on, it became more disappointing. The idea of doing things in 3D has been bounced here and there for a while in different forms but they didn't seam as limiting (and also not as cheap) as this.

• 512 million bits=64MB. Not miniscule, but not huge.
  
• WORM (write once read many). Yeah, you can use it for digital photography, but you can only use it once.
  
• It seemed like he was skirting the heat issue, only mentioning it briefly at the end.
  

This initial size doesn't bother me. As it's perfected and costs go down that would grow fast enough. Being WORM media is another issue though. I understand that this is a stepping stone to dynamic media, but at the moment I can get CD-Rs for around $.50/unit that are a proven media, hold much more data, and are already widely supported. And guess what: there are CD-RW already too (he can't do that yet). The heat thing could also be/not be an issue. Perhaps since it's stacked vert it will cool better. It's certainly harder to cover all surfaces in 3D. I have this vision of a cube with a heatsink on it's five exposed sides, only to have a core meltdown.

But is it a win?

[Animats]

The author writes: Fortunately, I and other engineers have recently found a way to skirt some of those obstacles, to give Moore's Law a new breath of life ... Such "three-dimensional" chips are now being commercialized by Matrix Semiconductor, a company I co-founded ... even for microprocessors, the sky is the limit.

Modest, he's not.

The problem, as someone else pointed out, is yield. This involves running the chip through all the steps of lithography, deposition, and etching many times, usually losing a few devices to process flaws on each pass.

That's why this guy talks about needing redundancy and error recovery. That's nothing new; as far back as the 1970s, chips have been designed with redundant parts that were bypassed during tests, like bad spots on disk. This works well for memory, badly for more complex logic. Historically, the semiconductor industry has considered redundancy, but the wafer fab people always got the yields up to where it wasn't necessary.

It's clear that this will make memories smaller, but not necessarily cheaper. The number of fab steps per bit fabricated is equal or higher, not lower. Yes, there's a savings on the raw silicon, but that's not a big fraction of chip cost.

There's also the fact that RAM doesn't take up a significant volume in most current products. Maybe 1% of a PC's case volume is RAM chips. This guy is thinking not of PCs, but portable applications, which is probably right. There's also more price headroom on things like "memory sticks" and "flash cards" than on commodity RAM for computers.

Notice that he's also thinking of slow, low-duty-cycle applications, like storing music and video. That cuts the heat dissipation. Cooling the gates in the middle layers will be tough.