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Here are the overall grades I'll give to players that I post their scouting reports.
Andrew Luck, Stanford - 9.0
Robert Griffin III, Baylor - 8.2
Ryan Tannehill, Texas A&M - 6.6
Russell Wilson, Wisconsin - 5.6
Kirk Cousins, Michigan State - 5.4
Brandon Weeden, Oklahoma State - 5.0
Ryan Lindley, San Diego St. - 4.0
Nick Foles, Arizona - 3.8
Kellen Moore, Boise State - 3.2
Chandler Harnish, Northern Illinois - 2.6
Dan Persa, Northwestern - 2.3
Darron Thomas, Oregon - 2.0
Trent Richardson, Alabama - 8.3
David Wilson, Virginia Tech - 6.1
Bernard Pierce, Temple - 5.6
Doug Martin, Boise State - 5.2
LaMichael James, Oregon - 5.0
Chris Polk, Washington - 4.9
Isaiah Pead, Cincinnati - 4.8
Cyrus Gray, Texas A&M - 4.4
Marc Tyler, USC - 3.6
Edwin Baker, Michigan - 3.6
Terrence Ganaway, Baylor - 3.4
Bradie Ewing, Wisconsin - 4.0
Derrick Coleman, UCLA - 3.5
Chad Diehl, Clemson - 2.8
Cody Johnson, Texas - 2.5
Justin Blackmon, Oklahoma State - 7.6
Michael Floyd, Notre Dame - 7.0
Kendall Wright, Baylor - 6.7
Mohamed Sanu, Rutgers - 5.7
Rueben Randle, LSU - 5.6
Dwight Jones, North Carolina - 5.3
Nick Toon, Wisconsin - 5.1
B.J. Cunningham, Michigan State - 4.8
Jeff Fuller, Texas A&M - 4.5
Marvin Jones, California - 4.0
A.J. Jenkins, Illinois - 4.0
T.J. Graham, N.C. State - 3.7
Junior Hemingway, Michigan - 3.3
Jarrett Boykin, Virginia Tech - 3.1
Danny Coale, Virginia Tech - 3.0
Chris Owusu, Stanford - 2.7
Dwayne Allen, Clemson - 7.2
Coby Fleener, Stanford - 6.4
Orson Charles, Georgia - 5.6
Michael Egnew, Missiouri - 5.1
Evan Rodriguez, Temple - 3.7
George Bryan, N.C. State - 3.2
David Paulson, Oregon - 3.0
Rhett Ellison, USC - 2.9
Matt Kalil, USC - 7.5
Riley Reiff, Iowa - 6.9
Bobby Massie, Ole Miss - 5.4
Jonathan Martin, Stanford - 5.4
Zebrie Sanders, Florida State - 5.3
Nate Potter, Boise State - 4.4
Mitchell Schwartz, California - 4.3
Jeff Allen, Illinois - 3.5 (OG)
Matt Reynolds, BYU - 3.4
Josh Oglesby, Wisconsin - 2.6
Landon Walker, Clemson - 2.4
David DeCastro, Stanford - 7.6
Cordy Glenn, Georgia - 6.7 (OT)
Kevin Zeitler, Wisconsin - 5.9
Kelechi Osemele, Iowa State - 5.7
Senio Kelemete, Washington - 4.6
Blake DeChristopher, Virginia Tech - 2.7
Jaymes Brooks, Virginia Tech - 2.6
Al Netter, Northwestern - 2.6
Antoine McClain, Clemson - 2.4
Peter Konz, Wisconsin - 6.8
Ben Jones, Georgia - 5.7
David Molk, Wisconsin - 5.4
Philip Blake, Baylor - 3.9
David Snow, Texas - 2.3
Michael Brockers, LSU - 6.9
Alameda Ta'amu, Washington - 6.0
Jerel Worthy, Michigan State - 5.8
Kendall Reyes, Connecticut - 5.6
Brandon Thompson, Clemson - 5.5
Billy Winn, Boise State - 5.1 (3-4 DE)
Mike Martin, Michigan - 4.9
DaJohn Harris, USC - 4.0
Nicolas Jean-Baptiste, Baylor - 3.9
Derek Wolfe, Cincinnati - 3.7 (3-4 DE)
Kheeston Randall, Texas - 3.4 (3-4 DE)
Tydreke Powell, North Carolina - 2.4
Christian Tupou, USC - 2.3
Quinton Coples, North Carolina - 7.7
Whitney Mercilus, Illinois - 7.0 (OLB)
Nick Perry, USC - 6.6
Vinny Curry, Marshall - 6.5
Andre Branch, Clemson - 6.2 (OLB)
Chandler Jones, Syracuse - 6.1 (OLB)
Tyrone Crawford, Boise State - 5.2
Matt Conrath, Virginia - 3.2
Justin Francis, Rutgers - 3.2
Donte Paige-Moss, North Carolina - 2.8 (OLB)
Courtney Upshaw, Alabama - 7.1 (DE)
Zach Brown, North Carolina - 6.6
Shea McClellin, Boise State - 5.5
Cam Johnson, Virginia - 4.3 (DE)
Brandon Lindsey, Pittsburgh - 3.9
Josh Kaddu, Oregon - 3.6
Luke Kuechly, Boston College - 7.4
Donta' Hightower, Alabama - 7.4
Tank Carder, TCU - 5.4
Mychal Kendricks, California - 4.7
Chris Galippo, USC - 3.1
Max Gruder, Pittsburgh - 2.2
Morris Claiborne, LSU - 7.4
Dre Kirkpatrick, Alabama - 6.7
Chase Minnifield, Virginia - 6.0
Jayron Hosley, Virginia Tech - 6.0
Brandon Boykin, Georgia - 4.8
Casey Hayward, Vanderbilt - 3.9
Antonio Fenelus, Wisconsin - 3.4
Robert Blanton, Notre Dame - 3.0 (S)
Trevin Wade, Arizona - 2.7
Charles Brown, North Carolina - 2.6
Gary Gray, Notre Dame - 2.3
Mark Barron, Alabama - 7.3
George Iloka, Boise State - 4.5
Eddie Pleasant, Oregon - 3.7
Aaron Henry, Wisconsin - 3.6
Delano Howell, Stanford - 3.5
Eddie Whitley, Virginia Tech - 2.8
Tavon Wilson, Illinois - 2.4 (CB)
Blake Gideon, Texas - 2.2
Blair Walsh, Georgia - 2.6
Drew Butler, Georgia - 2.7
Brad Nortman, Wisconsin - 2.5
Kyle Wojta, Wisconsin - 2.4
Grading System
8.8-9.0 - Franchise Player. Player that can have an instant impact on the league as well as be the centerpiece of both an offense and defense. High character player that you can build around. Definitely a player you target with your No. 1 pick.
8.5-8.7 - Top Foundation Player. May not have the super high character, or may not be the perfect or prototypical physical tools, but an impact player that can make an instant impact as well as be a major building block for your team in the future. The type of player you target with a Top 3 pick.
8.0-8.4 - Foundation Player. Will be a key building block player. Typically a super-talented player that may not have ideal character or intangibles. BUt should be able to contribute right from the start, even if it's as a role player, but in a short time should be contributing as a significant playmaker and matchup nightmare for opposing teams. The caliber of player that should be a perennial Pro Bowler. Definitely target with your Top 10 pick.
7.7-7.9 - Has the skillset to be a perennial Pro Bowler and be considered one of the top players at his respective position. Is usually a player with top athletic potential, but questionable character. Or a player that may not excel in the athletic department to stand out from the rest, but has the character and intangibles to think that he has a fairly low floor. Should be able to take on most of the top-level opponents and at the least hold his own. The type of player that you can accept taking in the Top 10, but definitely target with a Top 15 pick.
7.3-7.6 - Player that should be one of the better players at his position and has the potential to be an impact player most weeks. Should be considered one of the team's better players on that side of the ball, but doesn't have the elite potential to reliably dominate games and the top-level opponents. Tends to be players with high floors, but may not have super high ceilings. The type of player that you want to target with a Top 15-20 pick.
7.0-7.2 - A player that is good enough to start right away, but probably not good enough to be an immediate impact player and is probably better coming off the bench or as a situational player early on. Could have upside to develop down the road into a top player. Tends to be a player with lots of potential, but may have a fairly low floor to begin with. This is the ideal player you target in the first 25-30 picks of the draft.
6.7-6.9 - A good player that probably isn't a great fit to start right away. Has big potential to develop, but may need the better part of two years before he can hit that potential. Can be an impact player down the road, but because of the time it will take to develop him, it'd be considered a reach to take him before pick #20. Tend to target in the latter portion of the first round.
6.4-6.6 - A player that has the potential to develop into a capable starter, but won't be a guy that can impact on a consistent basis. Tends to be a player with good athletic potential, but may not be the best fit in your scheme to really maximize it. Tends to be seen more as a very skillful complementary option and player rather than a go-to playmaker. Good enough to compete for a starting position right away, but probably not a good bet to win it.
6.0-6.3 - A player with good upside that you expect to be a starter at some point, but probably not going to be able to contribute right away. Not polished enough to start right away, and may take the better part of three seasons before he starts to live up to his potential. A high upside player, but has a fairly low starting floor and a relatively long length to impact. Talented player, but probably not the best fit in your scheme to optimize his skillset.
5.7-5.9 - A player that has the potential to be a quality starter on your team, but isn't going to be a Pro Bowl player. Tends to be more of a complementary player that can be a capable starter, but probably is a bit too raw to think he can impact right away. Probably takes at least the better part of two years to develop as an impact player, but even when he does is probably not going to be an impact player. The type of player that you tend to target in the latter half of the second round.
5.4-5.6 - Quality players but don't quite have the skillset to excel in your scheme. Players that can be capable starters but won't be considered impact players. These are the players that you tend to target to fill out your starting lineup, but rarely have big games or impact performances. They tend to be capable complements to good players. You expect them to start, but won't be surprised if they don't play at a high enough level to merit an extension at the end of their rookie contract.
5.0-5.3 - These are players that could become starters for you, but more than likely you target them as really good role players and complements. Might be talented, but might have serious questions about size or athleticism to really be considered a reliable starter at the next level. They can definitely contribute on the next level, but you don't see them being anything more than average starters.
4.7-4.9 - These players are just on the cusp of where you think they can be starters. They have the potential, but are lacking in at least one key area that limits their potential. If they do become starters, you think they would make nice complementary options, but may not be talented enough to stick beyond their rookie contract, and if they do it's more likely to be as a role player.
4.4-4.6 - Good enough to be a starter at the next level, but if he does, he'll struggle to compete against the quality players at the next level. Not a player you want in a key position and tends to be more a stopgap option for a few years rather than a long-term solution. Best used as a role player.
4.0-4.3 - Has enough ability to potentially be a starter, but if he does develop it'll likely come after his rookie contract expires and he hits free agency. Tends to have ability and productive college player, but tends to be lacking in more than one key area that limit his upside to start on the next level.
3.7-3.9 - A player that may excel in one area that might give him limited upside as a starter, but lacking in most major necessary areas. Tends to be a player you prefer to target as key role players and quality depth rather than starting caliber players. If in a pinch, they can be a decent stopgap option, but not a player you want starting for more than a few games in a season.
3.4-3.6 - Definitely has the tools to stick on the NFL level as a reserve, but not quite of the skillset that he may have trouble sticking long-term with most teams. Tends to become journeymen. Have enough tools in most necessary areas that he should be able to contribute off the bench as a role player.
3.0-3.3 - Has enough tools to stick on the NFL level, but tend to be journeyman over the long haul and unless they can really form a niche as a reserve or special teams ability, they will have a hard time getting a second contract with a team. These players tend to provide depth, but if they are forced to start for more than a game or two, your team is going to be in trouble.
2.7-2.9 - These players may have enough in one area to think he might be able to contribute as a reserve, but more than likely, their ability to stick will largely depend on their ability to play on special teams. They can be developed as depth, but have almost no upside to be a starter. Only have enough upside that could be worked into the lineup as a situational player, but only likely to be used in that role if there is an injury.
2.4-2.6 - Might be a productive college player that is usually lacking in several key areas that make you think their ability to stick on the next level is limited. Usually players that can only play on special teams, and have the skillset to be effective there. But if he is asked to contribute offensively or defensively, he'll be overmatched in all but the most limited role.
2.0-2.3 - Players tend to be lacking in one critical area, whether it's size, speed, or athleticism to really think he can stick at the next level. Might be able to make an NFL roster, but not a player that is going to last for more than a year or two unless he can hammer out a significant role on special teams. More than likely, they'll be gone by the end of their third summer. A player that definitely has the potential to earn a practice squad role his first season, but not a guaranteed fit to make the roster.
1.5-1.9 - Player that has a severely limited skillset that makes developing him for even a reserve spot is a longshot. But a player that enough of a skillset to think he can compete and push another player for a reserve spot. Can make a practice squad at the outset, but more than likely will be among the roster cuts.
1.0-1.4 - Has enough skill that if things break his way can land a practice squad position, but has almost no real shot of making an NFL roster and lacks upside to be worth developing down the line. More of a player that you add purely to fill out a 80-man roster rather than because you think he has any real potential to develop.
Pudge's 2012 Position Rankings
The year's upcoming draft and the college game can be discussed here.
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Year of publication
- Sinotibetische Sprachen (10)
- Sinotibetische Sprachen (9)
- Tibetobirmanische Sprachen (8)
- Chinesisch (5)
- Qiang-Sprache (5)
- Tibetobirmanische Sprachen ; Nungisch (5)
- Nungisch (4)
- Drung (3)
- Philippinen-Austronesisch (2)
- Sprachkontakt (2)
- Topicalization and the question of lexical passives in Chinese (1988)
- This paper is one argument for a theory of grammatical relations in Chinese in which there are no grammatical relations beyond semantic roles, and no lexical relation-changing rules. As the passive rule is one of the most common relation changing rules cross-linguistically, in this paper I will address the question of whether or not Mandarin Chinese has lexical passives, that is, passives defined as in Relational Grammar (see for example Perlmutter and Postal 1977) and the early Lexical Functional Grammar (LFG) literature (e.g. Bresnan 1982), where a 2-arc (object) is promoted to a 1-arc (subject).
- Arguments against 'subject' and 'direct object' as viable concepts in Chinese (1993)
- Thirty-one years ago Tsu-lin Mei (1961) argued against the traditional doctrine that saw the subject-predicate distinction in grammar as parallel to the particular- universal distinction in logic, as he said it was a reflex of an Indo-European bias, and could not be valid, as 'Chinese ... does not admit a distinction into subject and predicate' (p. 153). This has not stopped linguists working on Chinese from attempting to define 'subject' (and 'object') in Chinese. Though a number of linguists have lamented the difficulties in trying to define these concepts for Chinese (see below), most work done on Chinese still assumes that Chinese must have the same grammatical features as Indo-European, such as having a subject and a direct object, though no attempt is made to justify that view. This paper challenges that view and argues that there has been no grammaticalization of syntactic functions in Chinese. The correct assignment of semantic roles to the constituents of a discourse is done by the listener on the basis of the discourse structure and pragmatics (information flow, inference, relevance, and real world knowledge) (cf. Li & Thompson 1978, 1979; LaPolla 1990).
- Parallel grammaticalizations in Tibeto-Burman : evidence of Sapir's 'Drift' (1994)
- In chapters seven and eight of his book Language, Sapir talked about what he called 'drift', the changes that a language undergoes through time [...]. Dialects of a language are formed when that language is broken into different segments that no longer move along the same exact drift. Even so, the general drift of a language has its deep and its shallow currents; those features that distinguish closely related dialects will be of the rapid, shallow currents, while the deeper, slower currents may remain consistent between the dialects for millennia. It is this latter type that Sapir felt is 'fundamental to the genius of the language' (p. 172), and he said that 'The momentum of the more fundamental, the pre-dialectal, drift is often such that languages long disconnected will pass through the same or strikingly similar phases' (p. 172).
- Variable finals in proto-Sino-Tibetan (1994)
- This paper concentrates on variable finals, and argues that just as we find a certain amount of both rule-governed and non-rule governed variation in modern languages, in reconstructing Proto-Sino-Tibetan we should recognize the possibility of these types of variation.
- On the change to verb-medial word order in proto-Chinese : evidence from Tibeto-Burman (1994)
- In attempting to reconstruct the morphosyntax of Proto-Sino-Tibetan, one of the most basic questions to be answered is what was the unmarked word order of the proto-language? Chinese, Bai, and Karen are verb-medial languages, while all of the Tibeto-Burman languages except for Bai and Karen have verb-final word order. lf these languages are all related, as we can assume from lexical correspondences, then either Chinese, Bai and Karen changed from verb-final to verb-medial word order, or the other Tibeto-Burman languages changed trom verb-medial to verb-final order. How we answer the question of which languages changed their word would then give us the answer to the question of word order in Proto-Sino-Tibetan.
- On the utility of the concepts of markedness and prototypes in understanding the development of morphological systems (1995)
- In attempting to understand the history of the morphology of a language or group of languages, we occasionally face a problem of isomorphy, where two or more semantic categories evince the same formal marking. We then must decide which use of that particular form of marking is the oldest, and also determine the possible source and path of development of the marking. In languages with written documents of great time depth this is often not a problem, but in unwritten languages it can be quite difficult. This paper discusses two tools that can be used for this purpose: the concepts of markedness and prototypes.
- Ergative marking in Tibeto-Burman (1995)
- This paper presents the first results of a comprehensive project on comparative Tibeto-Burman (TB) morpho-syntax. Data on morphological forms and typological patterns were collected from one hundred fifty-one languages and dialects in the TB family. For this paper the data were surveyed for nominal 'ergative' or agentive case marking (postpositions), in an attempt to determine if it would be possible to reconstruct an ergative case marker to Proto-Tibeto-Burman (PTB), and in so doing learn more about the nature of grammatical organization in PTB. Ablative, instrumental, genitive, locative, and other case forms were also surveyed for possible cognacy with ergative forms, as suggested in DeLancey 1984.
- Middle voice marking in Tibeto-Burman (1996)
- Middle voice marking is very rarely recognized as such in the grammars written on Tibeto-Burman languages. It is often simply treated as a normal direct reflexive or as an intransitivizer. In order to draw the attention of scholars to the existence and function of middle voice marking in Tibeto-Burman languages, the present paper discusses the form and function of middle marking in several of these languages. We will first discuss key facts about middle marking in general, then discuss the individual Tibeto-Burman examples.

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Deputy Prime Minister John Prescott to Grace CNU XV
Come hear Mr. Prescott discuss cities and sustainabilitySubmitted on 05/14/2007. Tags for this image:
The Congress for the New Urbanism is pleased to announce that Rt. Hon. John Prescott MP will be addressing the Fifteenth Congress for the New Urbanism in Philadelphia, Pennsylvania on Saturday May 19. Mr. Prescott will speak at the Saturday Evening Plenary along with other distinguished advocates for the urban form and urban planning principles. Mr. Prescott will discuss chiefly how sustainable cities will play an integral role in facing climate change in the context of a global economy.
The Deputy Prime Minister's participation at CNU XV will continue a tradition of productive dialogue with CNU members. Mr. Prescott has spoken at two previous Congresses, focusing on his support for sustainability, Brownfield development, and affordable housing throughout the United Kingdom and worldwide. After years as a tireless labor advocate, Mr. Prescott was appointed Deputy Prime Minister in the 1997 General Election. He has been an influential figure across a wide range of domestic policy initiatives, especially in the formation of the role of the Kyoto Treaty agenda in the UK. Mr. Prescott is sure to leave the audience at CNU XV with new ideas on citywide sustainability from a perspective outside of traditional domestic policy within the United States that speak to the role of sustainable cities both here and abroad.


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As of Sunday, July 1, 2012
© Copyright 2015 Albany Herald
EUGENE, Ore. — See ya in London, Angelo.
Albany native and former Georgia Tech track star Angelo Taylor, 33, made his staggering fourth U.S. Olympic team Sunday when he finished second in the 400-meter men's hurdle final behind James Tinsley.
Taylor, who is a two-time gold medalist in the event (2000 and 2008), led the entire race, but stumbled on the ninth hurdle — which was just enough to give up the lead. Although, he only needed to finish in the Top 3 to secure his spot on the Olympic team.
When asked afterward about the incredible feat of making four Olympic teams spanning nearly two decades — with a chance to become the first man to ever win three golds in the 400M should he leave London with the top honor again — Taylor said he 'Thanked the Lord," for all his success and added that he feels more motivated right now than at any point in his career.
"Not many people make it to their fourth Olympic team, so this is something that I really wanted to do," Taylor said. "I knew the competition I was facing. My main goal was just to stay healthy, and goal No. 2 was just to make the team."
Taylor really should've been talking about his wire-to-wire win in the finals afterward, rather than second place. Taylor burst out to a 10-stride lead after 200 meters and was leaving his competitors in the dust. But his fast pace caught up with him on the second-to-last hurdle and he clipped it just barely as he went over. That took Taylor briefly out of his stride and caused him to mistime the final hurdle ever-so-slightly, lose his lead and allow Tinsley to catch him.
Olympic silver medalist Kerron Clement finished third.
Taylor joined a lot of other American track stars Sunday on the next flight to London.
Wallace Spearmon dominated the men's 200 controversy-free with his easy victory.
Spearmon got off to a slow start, but recovered in time to win in 19.82 seconds Sunday at Hayward Field.
His victory — and his chance for redemption at the London Games after losing the bronze medal to disqualification in Beijing — was an expected finish to what should have been the conclusion to the trials.
RUNOFF FOR FINAL WOMEN'S 100M SPOT TONIGHT: Allyson Felix and Jeneba Tarmoh will run this afternoon to settle a third-place tie in the 100 for the final spot on the U.S. Olympic team.
Felix and Tarmoh finished in a dead heat for third in the 100 more than a week ago behind winner Carmelita Jeter and Tianna Madison, putting the team for the event in limbo. Track officials had no policy in place to resolve it but the next day devised a tiebreaker that included the options of a runoff or a coin flip.
The decision was put off eight days to allow Felix and Tarmoh to focus on the 200, which Felix handily won Saturday night. Tarmoh finished fifth. On Sunday morning the athletes got together with track officials and decided on the Monday runoff.
USA Track and Field was criticized because there was no tiebreaking policy in the first place and because the matter lingered for so long.
BLAKE GOES 2-FOR-2 VS. BOLT IN JAMAICA TRIALS, WINNING 200M SUNDAY: No posing, no salutes, no fist pumping. Yohan Blake simply paced in front of the jam-packed grandstand at National Stadium and stared up into the crowd, letting all those fans soak in a nice, long look.
This, ladies and gentlemen, is the man to beat at the London Olympics.
In a result that can no longer be considered a surprise, Blake beat Usain Bolt in the 200 meters at Jamaican Olympic trials Sunday, finishing in 19.80 seconds to edge the world-record holder by 0.03.
When it was over, Bolt was the first one to approach his training partner and buddy and give him a big bear hug.
"A lot of people gave me encouragement, said, 'Yohan Blake, you can do it,' " Blake said.
The win came two days after Blake, the reigning world 100 champion, beat Bolt in the 100 by running a 9.75.
That was a shocker, but there were explanations — most notably the terrible starts Bolt got off to throughout the 100 heats and in the final.
As they approached the finish line in the 200, Bolt was grimacing — or was that the hint of a frustrated smile — as he looked to his left to see what hardly anyone could have imagined earlier this week: Blake beating him to the finish line for the second time in the span of three days.
"I'll have to figure out what I did wrong and work on it," Bolt said.
In the women's 200, Shelly-Ann Fraser-Pryce ran a personal best 22.10 seconds to also complete the 100-200 sweep. She'll be joined by Sherone Simpson and two-time defending Olympic champion Veronica Campbell-Brown.
Sister_Ruby 3 years ago
Watched it on my little 13 inch tv. Good job, An'Jello.
coachjohnson42 3 years ago
Wow, Sister are you actually congratulating this young minority from Albany? Are you feeling ok? Whats wrong?
Cartman 3 years ago
What a racist venomous comment and cheap shot. Why would you ruin the comments of a positive sports story like Angelo's Olympic triumphs? Do you have something against positive role models like Angelo Taylor? Not only kids, but our whole community needs to hear more success stories like this one. Stories where hard work and dedication pay off - instead of corruption and cheating and loafing and free-loading. Why is race always the focus of your drivel? You think you have to be black to be proud of Taylor? I'd hate to live in your small world. You've got to quit reading Carlton Fletcher's articles.
coachjohnson42 3 years ago
I am just shocked at Sister Ruby's "change of heart" ....she normally criticizes minorities and puts them down.
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More like this story
- 2012 SUMMER OLYMPICS: Felix wins 200M gold in big day on track for U.S.A. ( August 8, 2012 )
- COUNTDOWN TO SUMMER OLYMPICS -- 6 days: Bolt-Blake rivalry adds intrigue to Olympic track ( July 20, 2012 )
- Zoom, zoom ( August 5, 2012 )
- History halted ( August 7, 2012 )
- OLYMPIC TRIALS: Southwest Georgia track stars Akins, Roulhac come up short of Olympic dreams ( July 1, 2012 )


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Simple to play, difficult to master and infuriating addictive! Destroy the atomic targets by flicking your detonation particles at them, but don't forget to check your solar wind indicator and make allowances. Don't waste time - your particles become more unstable by the second! Destroy all targets for big bonuses and see if you can beat the high scores and longest runs.


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Add warmth and style to any room with this compact pendant light. The design features an exclusive pattern designed by Southern California retro modern artist and illustrator Ragnar custom-printed on a translucent shade. This allows warm light to shine through, illuminating the pattern and creating a spectacular look. A white acrylic diffuser at the bottom prevents glare and provides even lighting. Includes energy efficient CFL bulbs. This stylish fixture is custom made to order. U.S. Patent # 7,347,593.
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A method for fabricating silicon-on-silicon substrates. A donor wafer (40) is attached to a target wafer (46) using a low-temperature bonding process. The low-temperature bonding process maintains the integrity of a layer of microbubbles (41). Subsequent processing separates a thin film (45) of material from the donor wafer. A high-temperature annealing process finishes the bonding process of the thin film to the target wafer to produce a hybrid wafer suitable for fabricating integrated circuit devices or other devices.
1. The process for fabricating a silicon-on-silicon wafer, said process comprising steps of:
providing one of a {100}, a {110}, or a {111} crystallographic plane single-crystal silicon donor wafer with a first polished surface;
implanting hydrogen or helium ions through said first polished surface to a first depth to form a layer of microbubbles;
bonding the first polished surface of the donor wafer to a second polished surface of a single-crystal silicon target wafer at a bonding temperature less than about 500° C., including activating the first and second polished surfaces by plasma cleaning and bringing the first and second surfaces into contact with each other to form an intermediate wafer assembly;
heating the intermediate wafer assembly to separate a thin film of material from the donor wafer, the thin film adhering to the target wafer to form a hybrid substrate assembly; and
annealing the hybrid substrate assembly to strengthen the bond between the thin film and the target wafer and to create electrical contact between the thin film and the target wafer.
2. The process of claim 1 wherein the plasma cleaning includes producing a plasma with a gas selected from the group consisting of argon, ammonia, neon, water vapor and oxygen.
3. The process of claim 1 wherein the step of annealing the hybrid substrate assembly is a continuation of the step of heating the intermediate wafer assembly.
4. The process of claim 1 further comprising a step, after the step of heating the intermediate wafer assembly, of polishing a separated surface of the hybrid substrate assembly.
5. The process of claim 1 wherein said {100} crystallographic plane is parallel to said first polished surface.
6. The process of claim 1 wherein said {110} crystallographic plane is substantially parallel to said first polished surface.
7. The process of claim 1 wherein said {111} crystallographic plane substantially parallel to said first polished surface.
8. The process of claim 7 wherein said {111} crystallographic plane is about three degrees from said first polished surface.
This application claims priority from the provisional patent application entitled A CONTROLLED CLEAVAGE PROCESS AND RESULTING DEVICE, filed May 12, 1997 and assigned application No. 60/046,276, the disclosure of which is hereby incorporated in its entirety for all purposes. This application is being filed on the same date as related application Ser. No. 09/025,966, now U.S. Pat. No. 6,048,411 entitled "A SILICON-ON-SILICON HYBRID WAFER ASSEMBLY" and application No. 09/028,870, pending entitled "A SILICON-ON-SILICON WAFER BONDING PROCESS USING A UNIFORM THIN FILM"
The present invention relates to the manufacture of substrates. More particularly, the invention provides a technique for manufacturing a silicon-on-silicon substrate assembly. The assembly consists of two substrates that are bonded together for use in the fabrication of a substrate for semiconductor integrated circuits, for example. But it will be recognized that the invention has a wider range of applicability; it can also be applied to other substrates for multi-layered integrated circuit devices, three-dimensional packaging of integrated semiconductor devices, microelectromechanical systems ("MEMS"), sensors, actuators, solar cells, biological and biomedical devices, and the like.
Wafers for electronic device fabrication are often cut from an ingot, or boule, of material with an abrasive saw. The wafer often serves as both a mechanical substrate and a semiconductor material to form electronic devices in or on. One of the most common examples of this is cutting silicon wafers from a silicon ingot. The wafers are typically polished to a very fine surface finish after "lapping" the wafer to remove the mechanical damage left by the abrasive saw, and after "backlapping" the other side of the wafer to remove saw damage and to produce a wafer of the desired thickness. In some processes, devices are fabricated directly in or on the silicon wafer. In other processes, a layer of semiconductor material is grown, for example by epitaxy, on the wafer. An epitaxial layer may provide lower impurity concentrations, or be of a different semiconductor type than the wafer. The devices are formed in what is known as the "active" layer, which is typically only a micron or so thick.
Epitaxial layers have been used successfully on smaller wafers and for smaller devices. Unfortunately, epitaxial layers have some associated problems that critically affect wafer yield and device yield as the size of either the wafer or the device increases. Epitaxial layers that are grown on a substrate typically adopt the crystalline structure of the substrate. In most cases, the substrate is a single crystal of a particular orientation. However, the most favored crystallographic orientation for growing an epitaxial layer may not be the most favored crystallographic orientation for forming semiconductor devices. Additionally, surface defects or contamination on the surface of the substrate can lead to "pipes", "spikes", and other types of defects in the epitaxial layer. Often, a single defect will ruin a particular circuit, or cell, on a substrate. As the size of the cells get bigger and more complex, the chance that any particular cell will fail because of a defect in the epitaxy layer increases. The size of the cells generally increase, given a particular processing technology, as the device count increases, which usually indicates an increase in circuit complexity and functionality.
The size of silicon wafers also continues to increase. Many state-of-the-art semiconductor devices are fabricated on 8-inch silicon wafers. Twelve-inch wafers are available, and the semiconductor fabrication industry is moving toward using wafers of this size, but, as with most changes in technology, must solve some problems first. One of the problems is that growing a high-quality epitaxial layer on a 12-inch wafer is very difficult. Some conventional processes do not have a sufficient yield of good wafers through the epitaxial growth process to make using a 12-inch wafer economically attractive. This problem is compounded by the cost of a 12-inch substrate, which can be over $1,000 per wafer.
From the above, it is seen that a technique for providing a substitute for an epitaxial layer that is cost effective and efficient is desirable.
According to the present invention, a technique for applying a thin film of silicon material to a target, or handle, wafer is provided. This technique separates thin films of material from a donor substrate by implanting gas-forming particles, such as hydrogen ions, into the donor substrate, to form a layer of microbubbles underneath a thin film of material, and then heating the microbubbles to create a pressure effect that separates the thin film of material from the donor substrate.
After implantation but before the thin film is separated from the donor wafer, the surface of the donor wafer is then attached to a target wafer, that will provide mechanical support for the thin film during the separation, or transfer, process. This bonding process is accomplished at a sufficiently low temperature so as not to initiate cracking in the microbubble region, or to deactivate the microbubbles by outgasing or diffusion. The target wafer can be a single crystal, polycrystalline, or amorphous, depending on the desired hybrid wafer characteristics.
The intermediate substrate assembly is then heated to create a pressure effect in the layer of microbubbles to separate the thin film, which is adhering to the target wafer, from the donor wafer. The thin film is then permanently bonded to the target wafer, typically with a high-temperature annealing process.
The present invention achieves these benefits and others in the context of known process technology. However, a further understanding of the nature and advantages of the present invention may be realized by reference to the latter portions of the specification and attached drawings.
FIGS. 1-3 are simplified diagrams illustrating a controlled cleaving technique according to an embodiment of the present invention;
FIGS. 4-6 are simplified diagrams illustrating a blister-separation technique according to another embodiment of the present invention; and
FIGS. 7-11 are simplified diagrams illustrating a method of forming a silicon-on-insulator substrate according to the present invention.
The present invention provides a technique for removing a high-quality thin film of material from one substrate and permanently bonding it to another substrate. The thin film of material forms a hybrid substrate with the second substrate and can substitute for an epitaxial layer on a conventional wafer. The invention will be better understood by reference to the Figs. and the descriptions below. The description begins with explanations of thin film removal processes before discussing the wafer bonding processes and resultant structures.
1. Controlled Cleaving Techniques
In a controlled cleaving process, a cleave is initiated by subjecting the material with sufficient energy to fracture the material in one region, causing a cleave front, without uncontrolled shattering or cracking. The cleave front formation energy (Ec) must often be made lower than the bulk material fracture energy (Emat) at each region to avoid shattering or cracking the material. The directional energy impulse vector in diamond cutting or the scribe line in glass cutting are, for example, the means in which the cleave energy is reduced to allow the controlled creation and propagation of a cleave front. The cleave front is in itself a higher stress region and once created, its propagation requires a lower energy to further cleave the material from this initial region of fracture. The energy required to propagate the cleave front is called the cleave front propagation energy (Ep). The relationship can be expressed as:
Ec =Ep +[cleave front stress energy]
A controlled cleaving process is realized by reducing Ep along a favored direction(s) above all others and limiting the available energy to be below the Ep of other undesired directions. In any cleave process, a better cleave surface finish occurs when the cleave process occurs through only one expanding cleave front, although multiple cleave fronts do work.
This technique uses a relatively low temperature during the controlled cleaving process of the thin film to reduce temperature excursions of the separated film, donor substrate, or multi-material films according to other embodiments. This lower temperature approach allows for more material and process latitude such as, for example, cleaving and bonding of materials having substantially different thermal expansion coefficients. The energy or stress in the substrate is limited to a value below a cleave initiation energy, which generally removes a possibility of creating random cleave initiation sites or fronts. This reduces cleave damage (e.g., pits, crystalline defects, breakage, cracks, steps, voids, excessive roughness) often caused in pre-existing techniques. Moreover, a controlled-cleavage method reduces damage caused by higher than necessary stress or pressure effects and nucleation sites caused by the energetic particles as compared to other techniques.
FIG. 1 is a simplified cross-sectional view diagram of a substrate 10 according to the present invention. As merely an example, substrate 10 is a is a single-crystal silicon wafer which includes a material region 12 to be removed, which is a thin relatively uniform film derived from the substrate material. The silicon wafer 10 includes a top surface 14, a bottom surface 16, and a thickness 18. Substrate 10 also has a first side (side 1) and a second side (side 2) (which are also referenced below in the Figs.). Material region 12 also includes a thickness 20, within the thickness 18 of the silicon wafer.
Hydrogen ions are implanted 22 through the top surface 14 of the silicon wafer to a selected depth 24, which defines the thickness 20 of the material region 12, termed the thin film of material. The ions can be implanted by a variety of techniques, including beam line ion implantation, plasma immersion ion implantation ("PIII"), or ion shower. Beam line ion implantation can be performed with equipment manufactured from companies such as Applied Materials, Eaton Corporation, Varian, and others. Examples of plasma immersion implantation techniques are described in "Recent Applications of Plasma Immersion Ion Implantation," Paul K. Chu, Chung Chan, and Nathan W. Cheung, SEMICONDUCTOR INTERNATIONAL, pp. 165-172, June 1996, and "Plasma Immersion Ion Implantation--A Fledgling Technique for Semiconductor Processing,", P. K. Chu, S. Qin, C. Chan, N. W. Cheung, and L. A. Larson, MATERIALS SCIENCE AND ENGINEERING REPORTS: A REVIEW JOURNAL, pp. 207-208, Vol. R17, Nos. 6-7, (Nov. 30, 1996), which are both hereby incorporated by reference for all purposes.
Hydrogen ions are desirable because they easily travel through the substrate material to the selected depth without substantially damaging the material region that the particles traverse through. The particles can also be derived from compounds such as gases, e.g., hydrogen gas, water vapor, methane, and hydrogen compounds, and other light atomic mass particles. Alternatively, other ions or combinations of ions may be used, depending on the material of the donor substrate, the thickness of the film to be removed, and the acceptable level of damage remaining in the thin film after processing.
Implantation dose ranges from about 1015 to about 1018 atoms/cm2, and preferably the dose is greater than about 1016 atoms/cm2. Implantation energy ranges from about 1 KeV to about 1 MeV , and is generally about 50 KeV. Implantation temperature ranges from about -200 to about 600° C., and is preferably less than about 400° C. to minimize escape of the implanted particles (e.g. via the diffusion mechanism). The hydrogen ions can be selectively introduced into the silicon wafer to the selected depth at an accuracy of about +/-0.03 to +/-0.05 microns.
Effectively, the implanted particles add stress or reduce fracture energy along a plane parallel to the top surface of the substrate at the selected depth. The energies depend, in part, upon the implantation species and conditions. These particles reduce a fracture energy level of the substrate at the selected depth. This allows for a controlled cleave along the implanted plane at the selected depth.
FIG. 2 is a simplified energy diagram 200 along a cross-section of the implanted substrate 10 according to the present invention. The diagram is merely an illustration and should not limit the scope of the claims herein. The simplified diagram includes a vertical axis 201 that represents an energy level (E) (or additional energy) to cause a cleave in the substrate. A horizontal axis 203 represents a depth or distance from the bottom of the wafer to the top of the wafer. After implanting particles into the wafer, the substrate has an average cleave energy represented as E 205, which is the amount of energy needed to cleave the wafer along various cross-sectional regions along the wafer depth. The cleave energy (Ec) is equal to the bulk material fracture energy (Emat) in non-implanted regions. At the selected depth 20, energy (Ecz) 207 is lower since the implanted particles essentially break or weaken bonds in the crystalline structure (or increase stress caused by a presence of particles also contributing to lower energy (Ecz) 207 of the substrate) to lower the amount of energy needed to cleave the substrate at the selected depth. This takes advantage of the lower energy (i.e. increased stress) at the selected depth to cleave the thin film in a controlled manner. If necessary, the cleave energy can further be reduced by subjecting the wafer to an intermediate thermal step below 500° C.
FIG. 3 is a simplified cross-sectional view of an implanted substrate 10 using selective positioning of cleave energy according to the present invention. This diagram is merely an illustration, and should not limit the scope of the claims herein. The implanted wafer undergoes a step of selective energy placement or positioning or targeting which provides a controlled cleaving action of the material region 12 at the selected depth. In this instance, the impulse is localized heating provided by a laser, although other heat sources, such as a heat lamp, or cold sources can be utilized. In another embodiment, a mechanical impulse is provided by twisting the target substrate with respect to the donor substrate, which generates maximum stress at the perimeter of the assembly, and minimum stress at the center. Of course, the type of source used depends upon the application.
Before locally heating the assembly, the stress in the implanted region was increased toward the energy level necessary to initiate the cleaving action without initiating the cleaving action. The global energy state of the substrate was raised by heating one side of the substrate to an intermediate temperature of about 350° C. with a heat lamp, or the substrate can be cooled, or differentially heated or cooled, that is a thermal gradient may be established across the assembly.
The removed material region provides a thin film of silicon material for processing. The silicon material possesses limited surface roughness and desired planarity characteristics for use in a silicon-on-silicon substrate. In certain embodiments, the surface roughness of the detached film has features that are less than about 60 nm, or less than about 40 nm, or less than about 20 nm. Accordingly, the present invention provides thin silicon films which can be smoother and more uniform than other techniques.
2. A Blister-Separation Method
FIGS. 4-6 are simplified cross sections of a thin film of material being separated from a wafer according to a blister-separation method, such as a process known as "Smart Cut." An example of an implantation blister-separation method is described in U.S. Pat. No. 5,374,564, entitled Process For The Production of Thin Semiconductor Material Films, by Michel Bruel, issued Dec. 20, 1994.
FIG. 4 shows a monocrystalline donor wafer 40 with a blister layer 41. The blister layer was formed by implanting hydrogen into the donor wafer, which is oriented such that a crystalline plane, or cleavage plane, is approximately parallel to the blister layer. For example, a dose of about 1016 cm-2 hydrogen ions implanted into a {100} silicon wafer at 150 KeV formed a blister layer approximately 1.2 μm below the top surface 42 of the donor wafer 40. It is believed that the implanted hydrogen ions capture electrons to form hydrogen atoms, which in turn form diatomic hydrogen gas. Heat treating the implanted donor wafer at a temperature about 500° C. forms a layer of microbubbles in the blister layer, which is parallel to a cleaving plane of the donor wafer, without causing the donor wafer to split. This heat treatment may be performed during the ion implantation, or may be performed as a separate step after the ion implantation, depending on the substrate temperature during implantation, among other factors. When the wafer is heated above about 500° C., gas pressure builds within the blister layer, and a thin layer 45 of the donor wafer will split off along the cleavage plane. It is believed this separation occurs because a crystalline rearrangement and coalescence of the microbubbles occurs to form macrobubbles with sufficient kinetics to separate the thin film from the donor wafer. Though a {100} crystallographic plane silicon wafer was used, the present invention contemplates the use of a {110} or a {111} crystallographic plane silicon wafer as well.
While gases other than hydrogen may be used, such as helium, neon, krypton, and xenon, hydrogen is advantageous. The braking process of hydrogen ions in silicon is predominantly an electronic, rather than nuclear, phenomena. This allows for a relatively high dosage to be implanted with relatively little damage to the silicon lattice, as compared to implanting similar doses of heavier ions. The electronic braking also provides a smaller range of distribution of implanted ions than would typically be obtained when implanting a heavier ion. This makes it possible to obtain suitable blister formation at a moderate implanted dose, and to separate a layer of silicon with a relatively smooth surface.
The thickness of the thin layer may be determined by appropriately choosing the implant energy. The expected thickness in {100} silicon has been calculated using the public-domain "TRIM" modeling software developed by J. Zeigler, as shown in Table 1.
TABLE 1______________________________________ENERGY (KeV) 10 50 100 150 200 500 1000______________________________________Film Thickness (μm) 0.14 0.5 0.88 1.27 1.72 5.59 15.67______________________________________
FIG. 5 shows a target wafer 46 bonded to the donor wafer 40. The target wafer provides support to the thin film 45 of silicon that will be blistered off of the donor wafer. The target wafer is a silicon wafer. The donor wafer may be bonded to the target wafer by a variety of methods, as described above. As above, it is desirable that the bonding method used not induce separation of the thin film unless that separation is intended. After bonding, heat treating the wafer assembly causes pressure to build up in the hydrogen gas bubbles that have formed in the donor substrate, to separate the top layer of silicon (about 1-15 microns thick) from the donor wafer. The bonding, heat treating, and annealing can be performed in a continuous thermal process, if desired.
FIG. 6 shows the thin film 45 of silicon attached to the target wafer 46 after separating the thin film from the donor wafer.
3. Silicon-On-Silicon Process
A process for fabricating a silicon-on-silicon substrate according to the present invention may be briefly outlined as follows:
(1) Provide a donor silicon wafer with a highly polished surface;
(2) Introduce particles into the silicon wafer through the highly polished surface to a selected depth to define a thickness of silicon film;
(3) Provide a target substrate material with a highly polished surface;
(4) Prepare the surface of the donor wafer and/or the surface of the target wafer for beta bonding the donor wafer to the target wafer (optional);
(5) Beta bond the donor silicon wafer to the target substrate material by joining the two highly polished surfaces;
(6) Separate a thin film of material from the donor substrate, the thin film of material adhering to the target substrate;
(7) Anneal the hybrid substrate of the thin film and the target substrate to complete bonding of the two layers together;
(8) Polish a surface of the thickness of silicon film (optional).
This sequence of steps is merely an example and should not limit the scope of the claims defined herein. Further details with regard to the above sequence of steps are described in below in references to the Figs.
FIGS. 7-11 are simplified cross-sectional view diagrams of substrates undergoing a fabrication process for a silicon-on-silicon wafer according to the present invention. The process begins by providing a semiconductor substrate similar to the silicon wafer 2100, as shown by FIG. 7. Substrate or donor includes a material region 2101 to be removed, which is a thin relatively uniform film derived from the substrate material. The silicon wafer includes a top surface 2103, a bottom surface 2105, and a thickness 2107. Material region also includes a thickness (z0), within the thickness 2107 of the silicon wafer above a layer 2111 of hydrogen ions or microbubbles, depending on the process used.
Hydrogen ions 2109 are implanted through the polished top surface of the silicon wafer to a selected depth, which defines the thickness of the material region, termed the thin film of material. As shown, the hydrogen ions (or microbubbles, depending on the process) have a desired concentration 2111 at the selected depth (z0). A variety of techniques can be used to implant the ions into the silicon wafer. These techniques include ion implantation using, for example, beam line ion implantation equipment manufactured from companies such as Applied Materials, Eaton Corporation, Varian, and others. Alternatively, implantation occurs using a plasma immersion ion implantation ("PIII") technique. Of course, techniques used depend upon the application.
The process uses a step of preparing the implanted donor silicon wafer to bond to a workpiece, or target, silicon wafer, as illustrated in FIG. 8. The silicon wafers are first "beta bonded" using a low temperature thermal step. Beta bonding is a relatively weak bonding process that joins the donor substrate to the target substrate. It is believed that beta bonding arises from electrostatic, or van der Waals, forces. Beta bonding produces a joint between the donor substrate and the target substrate for the target substrate to act as a mechanical support for the thin film when it is subsequently separated from the donor wafer. Beta bonding is generally not robust enough to join the thin film to the target wafer during subsequent wafer processing, such as lapping, polishing, or dicing operations, but is sufficient to hold the thin film to the target wafer until the assembly can be annealed and securely bonded.
Prior to beta bonding, the surfaces of the wafers are stripped of native or residual oxide and thoroughly cleaned, such as with an RCA-I and RCA-II cleaning sequence. An example of a solution used to clean the wafer is a mixture of H2 O2 --H2 SO4. A dryer dries the wafer surfaces to remove any residual liquids or particles from the wafer surfaces. In an alternative process, the clean silicon surfaces of the wafers are dipped in hydrofluoric acid.
The cleaned and/or activated surfaces are then pressed together under moderate pressure. Using a low temperature beta bonding process generally ensures that the implanted particles do not initiate a fracture, or not diffuse or outgas. In one aspect, the low temperature bonding process occurs by a self-bonding process.
Alternatively, a self-bonding process occurs by activating one or both of the wafer surfaces to be bonded by plasma cleaning. In particular, plasma cleaning activates the wafer surface using a plasma derived from gases such as argon, ammonia, neon, water vapor, and oxygen. It is believed that the plasma cleaning step activates the surface of the wafer by creating dangling silicon bonds. The activated target wafer surface 2203 is placed against a face of the donor wafer surface 2103, which will create a layer-to-layer interface. The wafers are in a sandwiched structure having exposed wafer faces, and the target wafer still has a desired concentration of particles 2111 intact. A selected amount of pressure is placed on each exposed face of the wafers to self-bond one wafer to the other.
After beta bonding the wafers into a substrate assembly 2300, as shown in FIG. 9, the target wafer 46 and the donor wafer 2100 are joined at a layer-to-layer interface 2305. The particles or microbubbles still form a separation region 2111 in the donor wafer. After beta bonding, the substrate assembly 2300 is processed to separate the thin film 2101 from the donor wafer 2100.
FIG. 10 shows a final bonding, or annealing, step occurs between the target wafer and thin film of material to form a hybrid wafer 2410. These embodiments often require high temperatures (e.g., above 700° C.). The final bonding step creates a strong bond between the thin film and the target substrate. It is believed that covalent bonds form between the two layers of silicon when the assembly is subjected to a sufficiently high temperature for a sufficient period of time, for example at 1,000° C. for approximately 1 hour. Lower temperatures generally require longer periods of time for the same degree of bonding to take place. During the annealing process, a thin film of thermal oxide 2406 may grow on the thin film 2101. The final bonding process provides an electrical contact between the thin film and the target wafer, as well as a robust mechanical bond that can withstand subsequent wafer processing.
Alternatively, the two silicon surfaces can be bonded by applying voltage between the two layers to establish a current flow through the hybrid wafer. The electric current heats the wafers to induce a bonding between the wafers. This technique limits the amount of crystal defects introduced into the silicon wafers during the bonding process, since substantially no mechanical force is needed to initiate the bonding action between the wafers. Damage may also be limited because the localized heating at the layer-layer interface is greater, due to increased series resistance in this region, than in the bulk of either the target substrate or the thin film.
After bonding the wafers, silicon-on-silicon has a target substrate with an overlying film of silicon material, as also illustrated in FIG. 10 The detached surface of the film of silicon material 2404 is often rough and may need finishing for some applications. Finishing occurs using a combination of grinding and/or polishing techniques. In some embodiments, such as when the thin film has been separated using a blister-separation method, the detached surface may undergo a step of grinding, or lapping, before the polishing step.
If the thin film was separated using a controlled cleavage process, the relative smooth and fracture-free surface allows chemical mechanical polishing or planarization ("CMP") techniques without a prior lapping step, as illustrated by FIG. 11. In CMP, a slurry mixture is applied directly to a polishing surface 2501 which is attached to a rotating platen 2503. This slurry mixture can be transferred to the polishing surface by way of an orifice, which is coupled to a slurry source. The slurry is often a solution containing a mild abrasive and an oxidizer, e.g., H2 O2, KIO3, or ferric nitrate. The abrasive is often very fine borosilicate glass, titanium dioxide, titanium nitride, aluminum oxide, aluminum trioxide, iron nitrate, cerium oxide, silicon dioxide (colloidal silica), silicon nitride, silicon carbide, graphite, diamond, and any mixtures thereof. This abrasive is mixed in a solution of deionized water and oxidizer or the like.
While the above is a full description of the specific embodiments, various modifications, alternative constructions and equivalents may be used. Therefore, the above description and illustrations should not be taken as limiting the scope of the present invention which is defined by the appended claims.
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Delaware Valley College's Aaron Karns and Zach Roseberry captured NCAA East Regional titles Sunday at King's College and will head a quartet of Aggie wrestlers to the NCAA Division III Championships, as the team placed third.
Karns, a senior 197-pounder, and Roseberry, a freshman heavyweight, will be joined by senior Emmanuel Ajagbe and junior Vinny Fava in Iowa in two weeks. Ajagbe was the 157-pound runner-up while Fava took third at 149 pounds.