Featured Research

from universities, journals, and other organizations

Crystal Growth Yields More Precise Semiconductors

Date:
November 22, 2001
Source:
University Of Wisconsin, Madison
Summary:
Sliced into almost paper-thin discs called wafers, semiconductors hold the circuitry that receives, transmits and processes information. Traditionally, scientists "grow" quantities of single-crystalline semiconducting materials by immersing the tip of a pencil-shaped starter crystal, or "seed," in a melt of the same composition. UW-Madison Materials Science and Engineering Professor Sindo Kou and graduate student Jia-Jie He have devised a method to ensure the melt composition stays constant.

Sliced into almost paper-thin discs called wafers, semiconductors hold the circuitry that receives, transmits and processes information.

Traditionally, scientists "grow" quantities of single-crystalline semiconducting materials by immersing the tip of a pencil-shaped starter crystal, or "seed," in a melt of the same composition. They then slowly withdraw and rotate the seed to form a thick rod shape. To make the crystal develop certain desired properties, they add special impurities to the melt before crystal growth.

However, as the crystal grows, it rejects those impurities into the melt or takes them in. As a result, the melt composition can change during growth - and since the crystal grows from the melt, the crystal composition can continue to change.

When the process is finished, the resulting crystal's composition and properties can vary along its length, so many parts built upon wafers from one crystal can be inconsistent in performance.

UW-Madison Materials Science and Engineering Professor Sindo Kou and graduate student Jia-Jie He have devised a method to ensure the melt composition stays constant.

They first lengthened the crucible in which the materials melt. Then they added a low-temperature heater around the crucible's lower half and moved the existing high-temperature heater to the upper half. The bottom of the crucible holds a solid material identical in composition to the desired crystal; the upper part holds the melt.

As the crystal grows and the melt level decreases, an existing mechanism pushes the crucible upward so that the solid material gradually enters the high-temperature heat zone, melts and keeps the melt composition constant.

Scientists can apply this method to crystals that are a mixture (an alloy) of two different semiconductors and grow them with a uniform composition. With a few modifications, users can adapt this technology easily to their existing equipment. Kou and He are patenting their discovery through the Wisconsin Alumni Research Foundation.


Story Source:

The above story is based on materials provided by University Of Wisconsin, Madison. Note: Materials may be edited for content and length.


Cite This Page:

University Of Wisconsin, Madison. "Crystal Growth Yields More Precise Semiconductors." ScienceDaily. ScienceDaily, 22 November 2001. <www.sciencedaily.com/releases/2001/11/011120052318.htm>.
University Of Wisconsin, Madison. (2001, November 22). Crystal Growth Yields More Precise Semiconductors. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2001/11/011120052318.htm
University Of Wisconsin, Madison. "Crystal Growth Yields More Precise Semiconductors." ScienceDaily. www.sciencedaily.com/releases/2001/11/011120052318.htm (accessed July 24, 2014).

Share This




More Matter & Energy News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com
Boeing Ups Outlook on 52% Profit Jump

Boeing Ups Outlook on 52% Profit Jump

Reuters - Business Video Online (July 23, 2014) Commercial aircraft deliveries rose seven percent at Boeing, prompting the aerospace company to boost full-year profit guidance- though quarterly revenues missed analyst estimates. Bobbi Rebell reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Car Market on the Rebound?

Europe's Car Market on the Rebound?

Reuters - Business Video Online (July 23, 2014) Daimler kicks off a round of second-quarter earnings results from Europe's top carmakers with a healthy set of numbers - prompting hopes that stronger sales in Europe will counter weakness in emerging markets. Hayley Platt reports. Video provided by Reuters
Powered by NewsLook.com
9/11 Commission Members Warn of Terror "fatigue" Among American Public

9/11 Commission Members Warn of Terror "fatigue" Among American Public

Reuters - US Online Video (July 22, 2014) Ten years after releasing its initial report, members of the 9/11 Commission warn of the "waning sense of urgency" in combating terrorists attacks. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins