Diamond semiconductor at 81GHz

[Chaotic42]

Not 8.1, but 81: From EETimes

 

[Schadenfroh]

show me the benchies

 

[DorkBoy]

what good does it do?

 

[DrPizza]

Wow, get some of the overclockers here to play with those chips... they'll be over 100 before you know it

 

[Mr.IncrediblyBored]

The joint team formed T-shaped gates on the diamond layer, which is on a 3-mm2 diamond substrate. The gate width, which determines the performance of devices, is 0.2 micron. The device operated continuously at 81 GHz. Once the peripherals technology is established, NTT researchers said they expect to boost the output power of the device as high as 30 W/mm, the level required for practical use.

This has been a major hurdle thus far with vapor deposition - building a wafer large enough to make a useable number of dice. Current fabs are manufacturing chips on 300mm in diameter wafers. It'll be another decade before we'll see wafers big enough to displace silicon. Source.

But the greatest potential for CVD diamond lies in computing. If diamond is ever to be a practical material for semiconducting, it will need to be affordably grown in large wafers. (The silicon wafers Intel uses, for example, are 1 foot in diameter.) CVD growth is limited only by the size of the seed placed in the Apollo machine. Starting with a square, waferlike fragment, the Linares process will grow the diamond into a prismatic shape, with the top slightly wider than the base. For the past seven years - since Robert Linares first discovered the sweet spot - Apollo has been growing increasingly larger seeds by chopping off the top layer of growth and using that as the starting point for the next batch. At the moment, the company is producing 10-millimeter wafers but predicts it will reach an inch square by year's end and 4 inches in five years. The price per carat: about $5.

 

[Chaotic42]

Yeah, this doesn't mean we'll have a P5 81GHz anytime soon. It's just an interesting direction that technology is taking.

 

[dude]

Should be in the market by next fall... winter at the latest. <sigh>

 

[Sachmho]

wait so is this a computer type chip, or like some broadcasting type frequency they're talking about... i dont quite get it

 

[Eli]

Originally posted by: Sachmho
wait so is this a computer type chip, or like some broadcasting type frequency they're talking about... i dont quite get it

It's a computer type chip.

It's gates have successfully been operated at 81,000MHz.

 

[Analog]

From the developers directly

The current target is to replace Vacuum Tubes:

A portable telephone needs only about 1 W at 1.5 GHz, but communication satellites and television broadcasting stations require 1 kW at 10 GHz (Fig. 1). In the 10-GHz frequency region, vacuum tubes are still used. However, vacuum tubes exhibit low energy efficiency, and thus a high energy loss.

For further information, contact:
Minako Sawaki, Hirofumi Motai
Planning Division
NTT Science and Core Technology Laboratory Group
Tel: 046-240-5152
E-mail: st-josen@tamail.rdc.ntt.co.jp

 

[Howard]

Why aren't wafers created square or rectangular?

 

[zzzz]

Originally posted by: Howard
Why aren't wafers created square or rectangular?

I am guessing for spin coating the resists.

 

[ScottyB]

Imagine how fast one can open Word with that processor.

 

[Mr.IncrediblyBored]

Originally posted by: Howard
Why aren't wafers created square or rectangular?

The primary reason wafers are round stems from how the wafers are created. They are essentially grown from a seed of pure silicon. This silicon seed is repeatedly dipped into a vat of molten sand, growing a bit with each successful immersion - not unlike dipping an apple into melted caramel. Eventually you'll get a cylinder shaped rod of silicon, known as the ingot, which will be cut, polished, and shipped to various fabs.

Secondly, with a round wafer, fab workers can fit more dice and with less waste than first having to cut the round wafers into a square or rectangular shape.

Cool article about how wafers are made.