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Saga 35
Saga 35 is designed for long, blue-water legs within a manageable framework
New on the Canadian front is an interesting little 35-footer designed by Robert Perry and built in St. Catharines, Ontario by Saga Marine. Unabashedly a cruising boat — in fact, dubbed by its developers as anything but a racer — it is designed to perform high up the curve nonetheless. And for a very specific reason: Passage-making speed, not racing speed, is the vessel's metier. Easy handling and comfortable accommodations for a couple on the go are primary objectives.
The new Saga 35 follows closely on the heels of the Saga 43 introduced in 1996, mirroring her big sister both in style and in spirit. It represents an important addition to the new-boat market in this popular size range. The 35 tweaks the mold in a number of innovative ways, most notably by suggesting that to cruise in comfort and to sail with pace and power are not mutually exclusive. The battle cry should sound familiar to most — it was enjoined by J Boats over a decade ago, and more recently by neo-BOC outfits such as Aerodyne (see our reports on the Aerodyne 38 in Blue Water Sailing March 1998 and the Aerodyne 46 in BWS June 1999).
Happily, Saga's spin on the concept is as original as these. Signature features include fairly narrow waterline beam; deep, stable canoe sections; plumb ends for maximum effective waterline length; and an unorthodox, if clever, double-head rig with a self-tacking masthead jib brought to the stemhead just inside a masthead reaching genoa that flies from the end of a bowsprit.
Rig/Deck Systems
The rig: The Saga imperative and designer Perry's charge were to make this boat, like the 43, as easy to handle as it is fun to sail. To that end, among the 35's more inventive details is the sailplan, a hybrid affair that falls under the general descriptive heading "enhanced sloop." Saga calls it the company's exclusive "Variable Geometry Rig," and as noted it includes two masthead forestays - one to the stemhead and one to the end of the bowsprit - and two purpose-specific jibs, a self-tacking 100-percent upwind blade and an overlapping reaching genoa.
The idea is this:Perry has placed the mainmast well forward in the boat, around station 3, which brings the center of effort forward, reduces the size of the foretriangle, and gives prominence to the mainsail. This allows the vessel to go nicely upwind with a small, 100-percent jib — precisely the sail deployed by the roller-furler on the after of the two headstays. The jib is virtually self-tending, trimmed as it is off a foredeck traveler by means of a single sheet led aft. The boat is balanced and happy upwind; tacking involves simply turning the wheel and watching the headsail slip across on its own.
Now, coming off the wind, you roll up the little jib and unfurl the reaching genoa that lives on the foremost of the two headstays. This heaps on the horsepower as you bear away, and the increase in sail area forward lightens the helm at the same time. In breezy trade-wind conditions a whisker-pole should stabilize the clew and provide days of controlled broad-reaching. In lighter air or when conditions warrant, roll up the genny and fly a loose-luff asymmetrical kite from the bowsprit.
The rig combines upwind versatility with offwind power. And in 35 feet, it makes a lot of sense. Were the boat configured as a conventional cutter, the staysail would have limited utility given its small size, and tacking around the intermediate forestay would be problematic. Trying to make one headsail on a single headstay do everything from 100-percent blade work upwind to 135-percent reacher work downwind is a bad idea. Saga's Variable Geometry arrangement provides a bit of headstay redundancy and an adaptable foretriangle.
In theory, it is not unlike what Walt Schulz at Shannon Yachts has been doing aboard his boats since 1994. In that year, he introduced the Shannon "scutter Rig," a similar sloop/cutter hybrid based, like Saga's, on the principle that no furling genoa can "do it all" over a wide range of wind strengths and wind angles. Schulz's version differs in that he places a furling genoa aft and a high-clew working jib forward. Nonetheless, the thinking is parallel. We will unravel the topic further next month in a report on the new Shannon 47.
Deck layout: Aboard the Saga 35, advantages gained in the realm of the deck layout are twofold. First, the self-tending feature of the small jib allows crew to operate the boat upwind almost exclusively from the safety and security of the cockpit, nestled aft and surrounded by welcome high coamings. Second, reduced demand for appearances on the bow by crew allows the cabin structure to extend forward without becoming a frequent obstruction, and this pays big dividends in the owner's cabin below in headroom and volume.
Hullform and Design
Perry's hull is narrower than a lot of what we see these days in modern yacht design, and he allows beam to taper back ever so slightly in the after sections, avoiding the tendency of many contemporary stylists to follow the lead of open-class ocean racers and put mini aircraft-carrier sterns on their cruising fare. A subtle and quite graceful sheer rises from stern to bow. The bow itself is virtually plumb, with a fine entry and a bit of hollow in the topsides that resolves itself in gentle flare as you move aft. To be sure, the hull itself is downright pretty.
A formidable stainless bowsprit cum anchor platform extends forward about two or three feet. Concessions made to the accommodations package below mandate a fair amount of cabin structure, but this is all for a worthy cause and, in truth, Perry has made a big effort to keep the profile under control and to avoid letting the boat become ungainly or top-heavy.
With reduced beam comes a perceived reduction in form stability, especially in conjunction with the modern-day penchant for flattened canoe sections and light displacement. The 35, however, shows relatively deep sections bow to stern — deep enough to carry 60 percent of the engine beneath the waterline — which is reassuring from a number of angles. In terms of stability and payload capability, volume underwater translates into a lower center of gravity, which reduces the need for exaggerated form stability and radical beam. As Olin Stephens cautions in the classic Desirable and Undesirable Characteristics of Offshore Yachts, "The way beam is used in combination with displacement and center of gravity is the crux of the stability question. Extremes are bad."
Furthermore, a deeper forefoot reduces pounding in seas and adds buoyancy forward. Increased deadrise along the length of the waterplane contibutes significantly to tracking, which allows Perry to go with a high-aspect keel (in the deep-keel version of the boat) to reduce wetted surface and optimize hydrodynamic lift. These factors help the vessel upwind and in close-reaching conditions, particularly by opposing leeward set. Also, as a result of the 35's plumb ends, she benefits from 34 feet of effective dynamic waterline length; in other words, hullform is at work through the water for virtually the entire length of the boat. In the spirit of promotion, Saga labels it their "MAX-Waterline" hull.
Construction & Numbers
Hull and deck are built conventionally of hand-laid fiberglass around Baltek balsa core. Resin content is monitored to achieve high strength-to-weight ratios. An ISO-NPG gelcoat is applied for resistance to osmotic blistering, followed by two layers of glass and vinylester, and then polyester in the remaining plies. The fabric of choice throughout the layup is non-woven bi-directional E-glass, a fairly straightforward, non-exotic way to go, combining good strength, low-crimp, light weight and reduced resin wet-out. Sensibly, coring is tapered to solid glass wherever through-hulls and hardware attachment occur.
Bulkheads and furniture are tabbed to hull and deck for monocoque structural integrity. The hull-deck joint occurs along a solid-glass inward flange. Finally, an elaborate, heavily reinforced E-glass subfloor grid stiffens the hull and accepts loading from the rig and external keel. No surprises here, just accepted, well engineered boatbuilding.
The finished product, in keeping with Saga's stated goals, appears to combine conservative seakeeping qualities with spry performance potential. Ballast/Displacement in the deep-keel boat tips in at 36 percent, healthy and upright by anyone's measure. Keeping the vessel to within 14,000 pounds, however, confers a Displacement/Length number of 162, certainly at the light and quick end of the spectrum for a cruising boat so well appointed as this.
A Sail Area/Displacement figure of 19.5 measured with 100 percent of the foretriangle connotes considerable horsepower and good light-air capability; with the abbreviated upwind jib, this number diminishes realistically to 17.5, a manageable yet hardly compromised mark that combines a comfortable ride upwind with the power and ability to claw effectively to weather in most conditions. In sum, given stout, lightweight construction and the designer's adeptness at efficient hullform with a conservative bent, this boat, at least on paper, appears to jump through a lot of hoops.
The 35 provides sensible accommodations for a couple with long-range voyaging aspirations. Hardly stripped out in the interest of unreasonable weight savings, the interior is spec"d with varnished cherry woodwork and joinery in all living compartments, and a varnished teak and holly cabin sole. An owner's cabin forward includes a generous double berth set obliquely against the starboard side, with a settee and cedar-lined hanging locker to port. The mainmast, being well forward, shares the cabin. Just aft of the berth is private access to the boat's single head and shower; general access is from the main saloon.
The saloon features longitudinal settees port and starboard flanking a fold-out dinette. Rigged with leecloths, either settee would make a stellar sea berth. Aft and on the port side is the galley, a U-shaped outboard-facing workstation with stove against the ceiling, reefer aft and double sinks forward as close to the boat's centerline as the turn of the U permits. Across the companionway and on the starboard side is a dedicated navigation station, available in an aft-facing configuration when the after cabin is selected as enclosed guest accommodations, or in a forward-facing configuration when the area aft is selected as an open navigator's quarter-berth.
Blue Water Thoughts
We like what Bob Perry and the crew at Saga have targeted with the Saga 35. They have taken the shorthanded voyaging theme developed in the 43 and put it in a more accessible package, which should appeal to plenty of long-range cruising sailors who find that small boats are where it's at. The vagaries of going to sea often delude people into thinking that bigger is better and safer. In truth, it's probably more comfortable over the long haul and faster, but lessons learned from countless blue-water sailors through the years suggest that seamanship has more bearing on safe passagemaking than waterline length alone.
That said, you do need a good boat to begin with. The Saga 35 has been developed from the ground floor up with blue-water voyaging and coastal cruising in mind. We like the vessel's athletic numbers; we also like the sensible if conservative elements of its design in terms of ultimate — not merely initial — stability.
We like the notion that this is not a race boat with a cushy interior, but rather a purpose-built cruiser with a cruiser's bells and whistles, one that just happens to have a very intentional performance edge. In concept and, presumably, in execution, the Saga 35 appeals to that part of us that wants to fly, but with broad and stable wings.
|Beam (max.)
|Beam (waterline)
|Draft (deep)
|Draft (shoal)
|Ballast (deep bulb)
|4,900 lbs.
|Ballast (shoal bulb)
|5,100 lbs.
|13,700 lbs.
|Sail area (100%)
|696 sq. ft.
|Sail area (w/tacking jib)
|626 sq. ft.
|Mast above water
|52' 6 "
|Ballast/Displ. (deep)
|Ballast/Displ. (shoal)
|SA/Displ. (100%)
|SA/Displ. (w/tacking jib)
|65 gal.
|80 gal.
|20 gal.
|Yanmar 3JH3E 38 hp diesel
|Base price
|$155,900 (FOB St. Catharines, Ontario)
Bob Perry
Robert H. Perry Yacht Designers
6400 Seaview Avenue NW
Seattle, WA 98107
phone: (206) 789-7212
fax: (206) 789-7214
Saga Marine
423 Lakeshore Road
St. Catharines, ON L2R 7K6
phone: (905) 646-4040
fax: (905) 646-2991


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Model Description: Batteries to replace the Emergi-Lite/Kaufel 002012
Compatibility: Emergi-Lite/Kaufel 002012
Condition: Brand new stock
Includes: Two new batteries, a set for the Emergi-Lite/Kaufel 002012
Warranty: 1 year full replacement warranty included, additional warranty is available.
Life time expectancy: 3-5 years
Manufacturer: UPS Battery Center Ltd.
The Emergi-Lite/Kaufel 002012 replacement battery pack consists of high quality sealed lead acid batteries that are designed to provide excellent performance and long life. This battery set meets and exceeds the original manufacturer's specifications.
Our batteries are new and always fresh stock. The Emergi-Lite/Kaufel 002012 battery pack is covered by our industry leading 1 year replacement warranty. Extended warranty of up to 3 years is available for your convenience. Our warranty is inclusive of shipping costs and is hassle free, the only warranty of this kind in the marketplace.
Physical Dimensions:(Individual Battery)
Voltage: 6 V
Capacity: 7Ah
Terminal Type: F1
Weight: 2.75 Lbs
Length: 5.95 "
Width: 1.34 "
Height: 3.70 "
The Emergi-Lite/Kaufel 002012 battery pack consist of (2) High Quality 6V 7Ah batteries.

subset: commoncrawl


text:
Johnny isn't talking at all at age two. But while he isn't using words yet, he's using babbling sounds and body language to communicate with the people around him. He's asking for what he wants, engages with other people, and enjoys playing with his parents and siblings.

Bobby is the same age as Johnny. Bobby does have a few words -- but he doesn't use them to communicate. Instead, he repeats them over and over to himself. Bobby has not yet figured out how to use gestures, sounds, or words to ask for something he wants. His parents find it almost impossible to hold his attention for more than a few seconds.

Johnny may have a speech delay that requires some form of early intervention. Bobby, however, despite the fact that he does have the use of a few words, may be exhibiting early signs of autism.

As typical babies develop, they quickly learn that communication is the key to getting what they want. Long before they learn to use spoken language, little ones make eye contact, pull on sleeves, babble, point, and otherwise work hard to get their point across to adults and older children. Over time, typical children learn to use spoken language because they get positive results from doing so.

Children with autism, however, according to the National Institutes of Health, may:

Fail or be slow to respond to their name or other verbal attempts to gain their attention

Fail or be slow to develop gestures, such as pointing and showing things to others

Coo and babble in the first year of life, but then stop doing so

Develop language at a delayed pace

Learn to communicate using pictures or their own sign language

Speak only in single words or repeat certain phrases over and over, seeming unable to combine words into meaningful sentences

Repeat words or phrases that they hear, a condition called echolalia

Use words that seem odd, out of place, or have a special meaning known only to those familiar with the child's way of communicating.

The bottom line?

Speech delays and differences are a hallmark of autism, and even those individuals who develop speech at a typical rate as toddlers may have a difficult time using spoken language effectively as they get older. They may use different vocal patterns, have a hard time reading or using body language, or continue to repeat sounds as a form of self-stimulation rather than as a means of communication.

Speech delays alone, however, are not an indication of autism. Speech delays and differences may be symptoms of many other disorders and delays, ranging from hearing issues to childhood apraxia of speech.

Learn More About Autism Symptoms, Types of Autism and Autism Diagnosis

Explore other symptoms of autism with the Autism Symptoms Checklist

Learn about different Types of Autism

Find out How Doctors Screen for and Diagnose Autism

Sources:

National Institute on Deafness and Other Communication Disorders. Article on Speech and Language. NIH Publication No. 00-4781 April 2000

National Institutes of Health. Is Baby Babbling on Schedule? Milestones in Speech and Language. NIH News in Health. September, 2007.

National Institutes of Health. A Parent's Guide to Autism Spectrum Disorder.


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Approximately 800,000 child deaths around the world each year could be prevented if every mother breastfed her child, according to a two-part study published in the Lancet.
The Guardian reports:
If almost every mother breastfed her children it could prevent more than 800,000 child deaths a year, yet governments are failing to promote and support breastfeeding, with rates remaining far below international targets, new research has found.
The benefits of breastfeeding are of course well-documented but despite this, only 37% of children under six months in "lower- and middle-income countries" are exclusively breastfed, according to the paper.
The suggestion is that women worldwide are not receiving the support needed to encourage them to breastfeed or continue with breastfeeding.
The series published in the Lancet was co-authored by the World Health Organisation and is the most comprehensive review of breastfeeding research.
We want to hear your thoughts on this research. Bearing in mind that it relates to world wide breastfeeding rates, what's your view? Do you agree that better support for breastfeeding mothers would improve the statistics? If you breastfed, what support did you receive? And if you didn't might better support have made a difference? Come and share your thoughts over on our Facebook page.
TOPICS: Parenting Tips


text:
Search billions of records on Ancestry.com
Carlow County -
Ireland Genealogical Projects (IGP
Lieutenant Colonel
Jim Breen
Lt. Col. Jim Breen,
former Army Press Officer,
served in the Defence Forces 1939-1974
Col Jim Breen was a former press spokesman and publicity
officer in the Dept. of Finance. During his term as senior
press officer at Army Hqrs he became well known and popular
with journalists throughout the country. He also served a
term as Personal Staff Officer to the then adjutant general
Maj. General James Flynn. a Portlaoise man. Because of his
wide experienced press relations he was seconded as press
officer to the newly established western development
committee, in 1969, He also had service-with the first Irish
speaking battalion in Kenmore. Galway.
Jim Breen lived al
Straw-hall. Athy Road. Carlow. He was educated at the
Christian Brothers Schools, primary and secondary, Carlow.
Source: Carioviana -
December. 1998 Page 81
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Bethel-Tate off to best beginning in county baseball
Bethel-Tate has opened the 2007 Clermont County high school varsity baseball season with the best start among the nine squads. The Tigers and Amelia were both unbeaten in the first full week of the campaign. Felicity is not fielding a team this year.
Head coach Jeff Dennis' Tigers mastered Madeira's Mustangs 4-2 behind Zach Taylor's five-hitter. Ryan Wagoner drove in the game winning run as he and Tommy Galea each had two hits.
McNicholas' Rockets, too, fell victim to the Red and Gray 3-1. Brannon fived a three-hitter at the Rockets. Galea scored two of the Bethel runs.
The Barons overpowered Western Brown's Broncos 11-5. Brandon Decker hurled the victory for the Blue and White. Amelia's attack was powered by Mike Stevens with four hits and two RBI, Brandon Huber with three hits and three runs batted in (RBI), Spencer Cox with two hits and three RBI, and Garret Hounshell and Vinny Terry added two hits apiece.
The Bulldogs lowered Loveland's Tigers 3-1 on Kris Hecktor's one-hitter. He helped himself with two hits and
J. D. Little had two more.
Deer Park's Wildcats downed the Bulldogs 7-5 as Ryan Beard took the loss on the mound supported by only two base raps from his teammates.
The Eagles outlasted Colerain's Cardinals in a Greater Miami Conference battle 9-8. Ryan Fulton was the winning pitcher. James Perry homered for the winners and drove in three runs, Steven Williams had two RBI and scored twice, and Jeremiah Aker and Ethen Daiker contributed two hits each. The Cardinals came back to avenge the first loss by beating Milford 7-4. Gregory Hickok took the mound loss. Williams had three hits and two RBI and John Benza hit safely twice.
Clermont Northeastern
The Rockets were overcome by Princeton's Vikings 11-7. Zach Hall was the losing pitcher. Trace Voshell homered for the Blue and Gold among his two hits, Seth Varner hit safely thrice and Justin Messinger twice.
Glen Este
The Trojans were defeated by Loveland's Tigers 10-7 in a Fort Ancient Valley Conference Buckeye Division showdown. Greg Jones made three hits and drove in three teammates and Nate Kline added two hits and two RBI for the Purple and White. Jerry Neeley absorbed the setback on the mound.
The Wildcats were nipped by Cincinnati Christian Cougars 3-2. John Pope led the 'Burg offense with two safeties. McAfee was the losing hurler.
The Warriors were whipped by Wilmington's Hurricanes 11-4. Kevin Hornsby homered for the Red and Gray and drove in three teammates to lead the Goshen offense. Chris Petry was the beaten pitcher.
Turpin's Spartans took the Warriors 6-3. Avery Smith, the losing pitcher, received only three hits from his mates in his support


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Customer Support
Maintenance How To Ensure a long cartridge life
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Maintenance: How to ensure a long cartridge life
To ensure a long cartridge life it is very important to purge the cartridge regularly. The cleaning cycle and purging cycle is NOT the same. Please refer to your printer manual for full instructions about purging your cartridge. What is a purge cycle? The purge cycle is an automatic process that heats all the tiny parts and ink in the cartridge and then cleans them from the inside out. All purge cycles produce a grid which consists of vertical and horizontal lines which represent printing quality of the cartridge.


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It was not so difficult to understand why Andrew Strauss wanted the insurance of a lead beyond 500. It is only three Tests ago that England declared and lost – in Chennai – and here he was confronted by one of the most destructive batsmen in the modern game, Chris Gayle.
Yet he encountered a defensive Gayle at the start of his innings and that can be an ominous sign for opponents, especially since he has become such a pivotal wicket when playing West Indies. When he starts defensively it suggests that he is at ease with the world and in those opening overs he scarcely picked up his bat.
Gayle often attacks with abandon because he is rattled. That was the case in the first innings. Andrew Flintoff ruffled him with several hostile, short deliveries. Steve Harmison tried to do the same. Gayle's instinct was to counterattack like a cornered wild beast and on Monday night, having sent one bouncer from Harmison on to the road outside, he then clubbed a drive in the air to mid-off and West Indies' totem was gone.
But at the start of the second innings there was no one to ruffle Gayle, with Flintoff standing dolefully at second slip, his hip rebelling, and Harmison grazing at mid-on. Stuart Broad tacked into a strong breeze nobly but on a sleepy pitch there was little chance of him peppering Gayle with short deliveries. At the other end Anderson sought swing but found none. Later Harmison did his best to rattle him, bending his back to get the ball shoulder high from this obstinate patch of turf.
So at first Gayle blocked, as still as a statue, biding his time. When a half-volley came his way he dispatched it and did not bother to run but otherwise he batted with a discretion that was rarely present before he was elevated to the captaincy.
England had to turn to Graeme Swann and initially the off-spinner posed few problems. There was the odd crisp cover drive and cut shot. No worries; Gayle was happy.
Then the think-tank set to work. Whether Swann, Strauss or the analysts behind the laptop were the architects, they came up with a scheme, which may have determined the outcome of the Test match, so important has Gayle's wicket become. The field was shuffled for the off-spinner. There were seven men on the off-side: a slip, a silly point, two men at short extra-cover and two men guarding the boundary at cover and long-off. This meant that there were acres of space on the leg-side. There were just Harmison at deep backward square-leg and Anderson at mid-on. England were tempting Gayle with those wide open spaces. He swept once with authority and the ball sped to the leg-side boundary. Strauss and Swann declined to change the field. Soon after he swept again, a more ungainly stroke with one hand off the bat but four more runs. The field remained unchanged.
Gayle may have been bemused by the impudence of the English. Why were they not plugging that gap? He would show them. He swept again; the ball hit his front pad, then after his usual, theatrical delay, umpire Rudi Koertzen slowly raised his finger. Gayle departed shaking his head. Perhaps he thought the ball was missing the stumps or that his front foot was outside the line. The truth was harder to bear: he had been outwitted.
So a topsy-turvy week for West Indies hinges on the last day. From the highs of Sabina Park, the humiliation of Friday's abandonment to the shock of Sir Allen Stanford's likely demise, the rudder has gone missing in spectacular fashion. Was it a coincidence that West Indies subsided on Tuesday just as news of Stanford's arrest became public?
Gayle, who has not looked especially interested in this match – though his demeanour has hardly been any different from what it was like in Jamaica – can only wait and watch now, hoping that his two little Guyanese stalwarts – Ramnaresh Sarwan and Shivnarine Chanderpaul – can retain West Indies' lead in the series. After all the upheavals a draw would be the equivalent of a victory for West Indies.


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|Publication number
|Publication type
|Application number
|Publication date
|Dec 8, 2009
|Filing date
|May 14, 2007
|Priority date
|May 14, 2007
|Fee status
|Also published as
|Publication number
|Albert Hasper
|Original Assignee
|Asm International N.V.
|Export Citation
|BiBTeX, EndNote, RefMan
|Patent Citations (101), Non-Patent Citations (12), Referenced by (7), Classifications (9), Legal Events (3)
|External Links: USPTO, USPTO Assignment, Espacenet
The present application relates generally to semiconductor processing, and more particularly to silicon and titanium nitride deposition.
The present application incorporates by reference the full disclosures of the following: U.S. Pat. No. 6,746,240; U.S. Pat. No. 6,962,859; U.S. Patent Application Publication No. 2003/0111013 A1; U.S. Patent Application Publication No. 2004/0250853 A1; U.S. Patent Application Publication No. 2005/0118837 A1; U.S. Patent Application Publication No. 2006/0060137 A1; U.S. Patent Application Publication No. 2006/0088985 A1; and Sze, VLSI T
High-temperature ovens, called reactors, are used to create structures of very fine dimensions, such as integrated circuits on semiconductor substrates. One or more substrates, such as silicon wafers, are placed on a substrate support inside the reaction chamber. Both the substrate and support are heated to a desired temperature. In a typical substrate treatment step, reactant gases (also referred to as precursors) are passed over the heated substrate, causing the deposition (e.g., chemical vapor deposition, or CVD) of a thin layer on the substrate. CVD is typically conducted at high temperatures, such as 250-900° C.
Deposition equipment normally includes a system for delivering gas to the reaction chamber. The gas delivery system typically comprises a plurality of precursor sources, optionally one carrier gas and/or purge gas source, a network of pipes for delivering the precursor gases to the reaction chamber, eventually an injection manifold or showerhead for injecting the gas evenly into the chamber, and a number of valves for controlling the gas flow. Also, some precursor sources may be in powder or liquid form, and means for vaporizing such precursors can be provided (e.g., bubblers).
Another type of deposition process is atomic layer deposition (ALD). In ALD, two complementary precursors are alternatively introduced into the reaction chamber. Typically, a first precursor will adsorb onto the substrate surface, but it cannot completely decompose without the second precursor. The first precursor adsorbs until it saturates the substrate surface; further growth cannot occur until the second precursor is introduced. Thus, the film thickness is controlled by the number of precursor injection cycles rather than the deposition time, as is the case for conventional CVD processes. Accordingly, ALD allows for extremely precise control of film thickness and uniformity. ALD is typically conducted at temperatures in a range 250-500° C.
In ALD, the reaction chamber is typically pulsed with a non-reactive protective gas between injections of the two precursor gases, in an attempt to rid the chamber of any excess of the preceding precursor gas. Otherwise, the excess preceding precursor would intermix and react with the subsequently pulsed precursor to form unwanted CVD-type growth on the substrate surface and/or on surfaces of the chamber.
For various reasons, including low electrical resistivity, good thermal stability, and good diffusion barrier properties, there are numerous applications for titanium nitride (TiN) in the fabrication of integrated circuits. Exemplary applications include use as a contact or barrier layer and as an electrode in electrical devices, such as transistors.
The properties of TiN, however, are closely dependent on processing and deposition parameters. Thus, the suitability and desirability of deposited TiN for a particular application can depend on the availability of a deposition process able to form TiN with desired properties, e.g., high uniformity and low resistivity. As a result, research into the development of new TiN deposition processes is on-going.
For example, the Low Pressure Chemical Vapor Deposition (LPCVD) of TiN films in a hot wall furnace has been described by N. Ramanuja et al. in Materials Letters, Vol. 57 (2002), pp. 261-269. The reach of Ramanuja et al. is limited, however, as Ramanuja et al. investigated 100 mm wafers, rather than industry standard 200 mm and 300 mm wafers.
In addition to being able to form acceptable TiN films, it is desirable for the deposition temperature of the TiN deposition process to be relatively low, thereby increasing flexibility for integrating the deposition process with other processes and structures. For example, reducing deposition temperatures to the 400-500° C. range allows the films to be used in conjunction with multi-level aluminum or copper metallization.
It has been found, however, that a reduction in the deposition temperature results in the incorporation of significant amounts of chlorine in the TiN film and results in a substantial increase in resistivity, which is undesirable. See J. T. Hillman, Microelectronic Engineering, Vol. 19 (1992), pp. 375-378. To reduce the resistivity and the chlorine content of the film, Hilman discloses a single wafer deposition process followed by a post-deposition anneal. Undesirably, however, such a process requires an additional process step and also limits throughput by using single wafer processing.
It is an object and advantage of the present application to provide viable methods for in situ deposition of TiN and silicon onto substrates in a batch reactor.
In one aspect, a method of processing semiconductor wafers is provided. A batch of semiconductor wafers is loaded into a processing chamber. Titanium nitride (TiN) is deposited onto the wafers in the processing chamber. Silicon is deposited onto the wafers in the processing chamber, without removing the wafers from the processing chamber between said depositing steps.
In another aspect, an apparatus comprises a processing chamber, titanium precursor source, nitrogen precursor source, silicon precursor source, and valve system. The processing chamber is configured to contain a plurality of semiconductor wafers. The titanium, nitrogen, and silicon precursor sources are each connected to the chamber to deliver a vapor of the titanium, nitrogen, and silicon precursor, respectively, into the chamber. The valve system is configured to allow selective control of delivery of the vapors into the chamber.
For purposes of summarizing the present application and the advantages achieved over the prior art, certain objects and advantages have been described herein above. Of course, it is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein.
All of these embodiments are intended to be within the scope of the invention. These and other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments having reference to the attached figures, the invention not being limited to any particular preferred embodiment(s) disclosed.
The invention will be better understood from the Detailed Description of the Preferred Embodiments and from the appended drawings, which are meant to illustrate and not to limit the invention, and wherein:
It has recently been found that uniform and low resistivity TiN films can be economically deposited onto substrates in a batch reactor by periodically introducing, or pulsing, one or more precursors into the reaction chamber of the reactor. For example, U.S. Patent Application Publication No. 2006/0060137 A1 to Hasper et al. discloses forming TiN films using stable titanium and nitrogen precursors, i.e., precursors that are not radicals or a plasma. Hasper et al. disclose two general methods: (1) alternately pulsing a titanium precursor (such as titanium tetrachloride, TiCl4) and a nitrogen precursor (such as ammonia, NH3) into the reaction chamber; and (2) continuously flowing one of the precursors (such as NH3) into the reaction chamber while pulsing the other precursor (such as TiCl4). Hasper et al. found that these methods allow for the deposition of TiN films with good uniformity and low resistivity on industry size wafers, such as 200 mm or 300 mm wafers. Furthermore, Hasper et al. found that such methods allow for TiN deposition at lower temperatures (e.g., between 450-600° C.), such that the deposition is compatible with other processes such as multi-level aluminum or copper metallization.
A TiN film is susceptible to oxidation. Typically, a protective polysilicon capping film is deposited onto the TiN film shortly after the TiN film is deposited, to protect the TiN film from oxidation. Current methods involve depositing the TiN and the silicon capping film in two different reactors, because silicon deposition is normally conducted at temperatures that are significantly higher than the preferred temperature range for depositing TiN (e.g., 450-500° C., as taught by U.S. Patent Application Publication No. 2006/0060137 A1 to Hasper et al.). A primary reason why TiN and silicon have been deposited in separate reactors, as opposed to depositing both layers at different temperatures within the same reactor, is because changes in temperature of a process tube used for depositing silicon (e.g., polysilicon) lead to unacceptable amounts of particle generation in the reaction chamber, which adversely affects the quality of deposited films. As well understood, the deposition of silicon onto substrates in a reaction chamber also results in silicon deposition onto the reaction chamber walls. It is usually the case that the deposited silicon and the chamber walls have different coefficients of thermal expansion. For example, radiantly heated reaction chambers are typically formed of quartz walls, and the coefficients of thermal expansion of quartz and silicon are 0.59 ppm/K and 2.3 ppm/K, respectively. If the temperature is varied significantly, the chamber walls and the silicon deposited thereon will expand and contract at different rates. This causes silicon particles to flake off of the walls, thereby contaminating the chamber. For this reason, it is generally not desirable to change the temperature in a reaction chamber used for silicon deposition.
This problem also arises when TiN and silicon are deposited at different temperatures as adjacent layers on substrates. TiN has a coefficient of thermal expansion of 9.3 ppm/K. Thus, if TiN is deposited at one temperature (e.g., 450-500° C.) and silicon is deposited onto the TiN at a significantly higher temperature, there would be an unacceptable risk of flaking and particle generation caused by the differential in thermal expansion and contraction of the silicon and the TiN.
Another reason why TiN and silicon have been deposited in separate reactors, as opposed to depositing both layers at different temperatures within the same reactor, is that it takes longer to wait for the temperature to change and stabilize throughout the chamber (particularly for a batch reactor) than it takes to transfer the one or more substrates to another chamber maintained at a different temperature. At the relatively low temperature used for TiN deposition, heat transport through radiation is limited. Heat transport by conduction is also not very efficient for a stack of substrates in a batch furnace at low pressure. Consequently, temperature stabilization is slow, and it is often less time consuming to transfer the substrates to another chamber.
The practice of depositing TiN and silicon in different reactors involves several problems and drawbacks. The need to transfer substrates between two separate reactors involves greater equipment costs and more complicated processing, and results in lower throughput. Further, while transferring the substrate with the TiN film from the TiN deposition reactor to a silicon deposition reactor, the TiN becomes exposed to air, which leads to an undesirable interface between the TiN and the silicon capping film.
Embodiments of the present application involve depositing a TiN film and an amorphous silicon capping film onto a plurality of substrates in a single batch reactor in situ, without removing the substrates from the processing chamber between these deposition steps. By depositing both films in the same reactor, it is possible to avoid the formation of an undesired interface between the TiN and the polysilicon capping film. The elimination of one reactor reduces costs. Also, the elimination of the intermediate substrate transfer step simplifies the processing logistics and increases substrate throughput.
"Substrate" is used herein in its usual sense to include any underlying surface onto which a material is deposited or applied. Preferred substrates include semiconductor wafers, such as silicon wafers. However, substrates can be made of virtually any material, including without limitation metal, silicon, germanium, plastic, and/or glass, preferably silicon compounds (including Si—O—C—H low dielectric constant films) and silicon alloys. Substrates can also have in them physical structures such as trenches or steps, as in a partially fabricated integrated circuit.
In some embodiments, the TiN deposition is conducted in accordance with the aforementioned methods taught by U.S. Patent Application Publication No. 2006/0060137 A1 to Hasper et al.: (1) alternately pulsing a titanium precursor (such as TiCl4) and a nitrogen precursor (such as NH3) into the reaction chamber, preferably with purge or evacuation steps therebetween; and (2) continuously flowing one of the precursors (such as NH3) into the reaction chamber while pulsing the other precursor (such as TiCl4). In other embodiments, the TiN deposition involves the following cyclical sequence: substantially simultaneous pulses of the titanium and nitrogen precursors, a purge or evacuation step, another nitrogen precursor pulse (referred to elsewhere herein as a "flush"), and then another purge or evacuation step. In some embodiments, both the TiN deposition and the polysilicon deposition are conducted at a relatively low temperature (e.g., 300-600° C., more preferably 400-500° C.). In preferred embodiments, trisilane (Si3H8) is used as a silicon precursor.
While the above discussion contemplates the in situ deposition of silicon capping films onto TiN films, in some embodiments the deposition sequence of the films is reversed, such that TiN films are deposited in situ onto previously deposited silicon films. For example, in
Batch Reactor
As mentioned above, the in situ deposition of TiN and silicon films is preferably conducted on a plurality of substrates, such as semiconductor wafers, in a batch reactor. Several exemplary batch reactors are now described.
Preferably, the batch reactor is configured or programmed to deliver one or more precursors in temporally separated pulses. The batch reactor preferably has a vertically extending reaction chamber that accommodates substrates vertically separated from each other, with major faces of the substrates oriented horizontally. Preferably, the reaction chamber accommodates at least 25 substrates, and more preferably at least 50 substrates.
With continued reference to
The process tube flange 90 can be maintained at an elevated temperature to avoid condensation of process gases on it. It will be appreciated that the elevated temperature can vary from process to process and is preferably chosen based upon the identities of the process gases (which, in some embodiments, are TiCl4, NH3, Si3H8, and N2). For example, the elevated temperature of the flange 90 is preferably above 120° C., preferably about 180-200° C. Regulation of the temperature of the flange 90 can be achieved by providing it with electrical heaters and a water-cooling system. The water-cooling is desired primarily to avoid overheating of the flange 90 during unloading of a batch of hot wafers 40.
Various systems can be used to supply reactants or precursors to the reaction chamber 20 (
Where the precursor, such as TiCl4, is stored as a liquid, a bubbler can be used to supply the precursor to the chamber 20 in gaseous form. The timing and rate of flow of such a precursor can be regulated by controlling the flow of carrier gas through the liquid in the bubbler and by controlling the temperature of the liquid. It will be appreciated that the quantity of the liquid precursor carried by the carrier gas increases with increasing temperature.
As noted above, process gases can be introduced into the chamber 20 in various ways. For example, in the reactor illustrated in
A multiple-hole injector is preferably not used to introduce a purge gas, however, because the top part of the reaction chamber 20 may be not effectively purged by an injector that only extends part way up the height of the chamber 20. Preferably, a purge gas is introduced into the chamber 20 at the chamber end that is opposite to the exhaust end, so that the purge gas flows through all regions of the reaction chamber 20 after entry and before being exhausted.
An additional injector 110 can be used for a purge gas, preferably an inert gas such as nitrogen gas. The injector 110 for the purge gas is preferably a tube with an open end at the top and without gas discharge holes in its sidewall, so that all the purge gas is discharged at the top of the reaction chamber 120.
In a preferred embodiment, inside the process chamber 526, gas is flowed in a generally upward direction 552 and then removed from the reaction space 529 via an exhaust space 554 between the process chamber 526 and the liner 528, where gas flows in a downward direction 556 to the exhaust 558, which may be connected to a pump (not shown). The gas injector 540 preferably distributes process gases inside the process chamber 526 over the entire height of the reaction space 529. The gas injector 540 itself acts as a restriction on the flow of gas, such that the holes 548 that are closer to the conduit 544 tend to inject more gas into the reaction space than those holes 548 that are farther from the conduit 544. Preferably, this tendency for differences in gas flows through the holes 548 can be compensated to an extent by reducing the distance between the holes 548 (i.e., increasing the density of the holes 548) as they are located farther away from the conduit 544. In other embodiments, the size of individual holes making up the holes 548 can increase with increasing distance from the conduit 544, or both the size of the holes 548 can increase and also the distance between the holes 548 can decrease with increasing distance from the conduit 544. Advantageously, however, the preferred embodiments are illustrated with holes 548 of constant size so as to minimize the surface area of the sides of the gas injector 540 containing the holes 548.
The injector 540 is advantageously designed to reduce the pressure inside the gas injector, resulting in a reduction of the gas phase reactions within the injector, since reaction rates typically increase with increasing pressure. While such reduced pressure can also lead to a poor distribution of gas over the height of the gas injector 540, the distribution of holes 548 across the height of the injector 540 is selected to improve uniformity of gas distribution.
The gas injector 540 is provided with a pattern of holes 548 substantially extending over the height 560 (
With reference to
The cross-section shown in
In a preferred embodiment, in a CVD mode, two precursor source gases, providing the two constituting elements of a binary film, are mixed in the gas supply system (not shown) prior to entering the gas injector 540 via feed conduit connections 545 and 546 (
Advantageously, the use of two gas injector parts 541 and 542 allows for further tuning possibilities. The flows supplied to the different gas injector parts 541, 542 can be chosen differently to fine-tune the gas flow into the reaction space 529. This will improve uniformity in the deposition rates of precursors over the height 560 of the wafer load 550 (
One skilled in the art will appreciate that further modifications to the batch reactor, or to the way of operating the batch reactor, known in the art, can be applied to improve the performance of this process. For example, it is possible to use a holder boat or ring boat (i.e., a wafer boat in which each wafer is individually supported by a separate wafer holder or ring-shaped holder inserted into the boat).
It will be appreciated that while the aforementioned hardware configurations are described in the context of pulsed CVD and ALD, they are equally suitable for use in the context of low pressure chemical vapor deposition (LPCVD).
TiN Deposition
It has been found that uniform and low resistivity TiN films can be deposited on wafers in a batch reactor by periodically introducing, or pulsing, one or more precursors into the reaction chamber of the reactor. Preferably, the TiN films are formed using stable titanium and nitrogen precursors, i.e., precursors which are not radicals or a plasma. More preferably, titanium tetrachloride (TiCl4) and ammonia (NH3) are used as the titanium and nitrogen precursors, respectively.
In one method, both precursors (e.g., TiCl4 and NH3) are alternately pulsed into the reaction chamber, preferably with intermediate purge gas injections or chamber evacuation steps. In this method (described below with reference to
The TiN deposition advantageously can be performed at a temperature of less than about 600° C. and, more preferably, at less than about 500° C., e.g., about 450-500° C. Thus, the deposition is compatible with other processes such as multi-level aluminum or copper metallization. In addition, the deposition can advantageously be used to deposit films on industry standard 200 mm and 300 mm wafers.
In some preferred embodiments, a stack of vertically-spaced substrates, e.g., semiconductors wafers, is accommodated in a batch reaction chamber and temporally separated pulses of the titanium and nitrogen precursors, such as TiCl4 and NH3, are supplied to the reaction chamber alternatingly and sequentially in an ALD of TiN.
The deposition rate of the TiN has been found to be particularly sensitive to variations in the gas partial pressure of NH3. As a result, NH3 is preferably flowed into the chamber using a gas injector having vertically distributed holes to allow an even distribution of the NH3. Preferably, each reactant is removed, e.g., by purging with an inert gas or evacuating the reaction chamber, before introduction of the other reactant. The duration of each of the pulses is preferably about 60 seconds or less, more preferably about 30 seconds or less, and even more preferably about 15 seconds or less.
When TiN films are formed by continuous CVD, by continuously flowing TiCl4 and NH3 into a reaction, the deposition rate of the TiN films has been found to not vary significantly with the partial pressure of the TiCl4. On the other hand, the deposition rate has been found to be approximately proportional to the partial pressure of the NH3. For depositing uniform films, these findings indicate that the mode of introduction and distribution of NH3 inside the reaction chamber is more important than that for TiCl4, whether or not NH3 is pulsed into the chamber, e.g., whether or not NH3 is used in an ALD or pulsed CVD process. As a result, as noted above, NH3 is preferably discharged into the reaction chamber in a manner that maximizes the evenness of the distribution of the gas into the chamber. In particular, NH3 is preferably discharged into the vertical furnace reaction chamber in a vertically distributed manner, e.g., through a multiple-hole injector having a plurality of vertically spaced apart holes, such as those discussed above. The injector preferably extends substantially over a height of the chamber, such that the holes of the injector span most or all of the vertical height occupied by the substrates. TiCl4 can also be discharged using the multiple-hole injector, or it can be discharged at a feed end of the reaction chamber (
In other preferred embodiments, the nitrogen precursor, e.g., NH3, is continuously supplied to the reaction chamber and only the titanium precursor, e.g., TiCl4, is supplied pulse-wise, resulting in CVD of TiN.
In still other preferred embodiments, each deposition cycle includes, in the following sequence, substantially simultaneous pulses of the titanium and nitrogen precursors, a purge or evacuation step, another nitrogen precursor pulse, and then another purge or evacuation step.
Advantageously, high quality titanium nitride films can be formed in accordance with the preferred embodiments. For example, the thicknesses of deposited titanium nitride films can vary by less than about 3 nm between substrates in a batch of substrates, and the resistivity can vary by less than about 5 μOhm·cm. Moreover, the films can be formed having a low resisitivity of about 220 μOhm·cm or less.
Advantageously, at lower deposition temperatures (e.g., 450° C.), the average film thickness across a wafer has been found to be exceptionally uniform from wafer to wafer, varying less than about 3 nm among the various wafers of a batch of wafers. At this temperature, the average resistivity of the films has been found to be advantageously uniform, varying less than about 5 μOhm·cm among the various wafers in the batch.
It is understood that precursor pulse time affects film thickness and resistivity. While longer pulse times would be expected to increase or possibly not affect the thickness of the deposited film in cases where the total TiCl4 exposure time was unchanged, it has been unexpectedly found that pulse times longer than about 30 seconds actually cause a decrease in average film thickness (in some experiments, from about 23.5 nm to about 23 nm). Even more unexpectedly, the average resistivity of the deposited film has been found to be strongly dependent on pulse times. In particular, in some experiments, film resistivity has been found to increase from about 220 μOhm·cm for TiCl4 pulse durations of about 15 seconds to about 520 μOhm·cm for TiCl4 pulse durations of about 60 seconds. Thus, shorter pulse times advantageously allow deposition of TiN films with reduced resistivity, e.g., about 220 μOhm·cm or less.
Where both reactants are pulsed, it will be appreciated that pulse times for both reactants can be the same or each can have a different pulse duration. Moreover, whether one or both reactants are pulsed, the duration of the pulses can remain the same throughout a deposition, or can vary over the course of the deposition.
In addition, the cycle duration can be selected to give a desired TiN film resistivity. For example, resistivities of about 520 μOhm·cm to about 220 μOhm·cm can be achieved by appropriately adjusting the TiCl4 pulse time (e.g., between about 15-60 seconds), or the duration of each cycle of process gases can be adjusted (e.g., between about 1-10 minutes).
Silicon Deposition
As discussed above, a silicon layer can be deposited onto the wafers in the batch reactor either before or after the TiN layer is deposited. The silicon layer may comprise amorphous silicon, and may be deposited by CVD, preferably at a low temperature or a temperature that is the same as or relatively close to the temperature at which the TiN layer is deposited. The deposited silicon and TiN layers can be deposited in direct contact with one another (e.g., immediately adjacent). The silicon layer may be deposited over the TiN layer so as to be a protective capping film. Alternatively, the TiN layer can be deposited over the silicon layer.
Between the steps of TiN deposition and silicon deposition, any excess precursor of associated with the earlier-deposited layer can be removed from the chamber by the injection of a purge gas, by a chamber evacuation process, by displacement of the earlier precursor gas by a gas carrying a reactive species, or any combination thereof. Where the earlier precursor gas is removed by purging, the process chamber is preferably purged for a duration long enough to replace the atmosphere in the chamber at least once.
A silane is preferably used as the silicon precursor. The silane can be selected from the group consisting of monosilane (SiH4), a polysilane and a chlorosilane (SiH4-nCln, where n=1 to 4). More preferably, a polysilane is used as the silicon precursor to form the silicon layer, discussed below. As used herein, a "polysilane" has the chemical formula SinH2n+2, where n=2 to 4. Preferably, the polysilane is disilane or trisilane. Most preferably, the polysilane is trisilane. Consequently, while embodiments of the invention are described in the context of employing CVD cycles with trisilane, the skilled artisan will appreciate, in view of the present disclosure, that certain advantages of the described processes can be obtained with other precursors and/or other deposition techniques.
Trisilane (H3SiSiH2SiH3 or Si3H8) offers substantial benefits when used as a silicon precursor, as disclosed in U.S. Patent Application Publication No. 2005/0118837 A1 and U.S. Pat. No. 6,962,859. For example, films can be deposited with trisilane at substantially lower temperatures than with other silicon precursors, such as silane (SiH4), which advantageously makes possible in situ deposition of both TiN and silicon in a low temperature range (e.g., 400-500° C.). Moreover, deposition rates with trisilane are relatively insensitive to substrate material and thickness. Also, trisilane has an extremely short film nucleation time, which reduces the size of localized crystalline deposits of silicon. As a result, deposited silicon films can be made thinner, while still being uniform. Moreover, the films will show reduced surface roughness due to the reduced size of the localized silicon deposits. In addition, with regards to process throughput, trisilane exhibits higher deposition rates relative to silane. Trisilane also reduces thermal budgets, since it allows use of lower process temperatures than does silane.
Thus, employing trisilane in the deposition methods described herein provides numerous advantages. For example, these deposition methods enable in situ deposition of TiN and silicon layers in a single reaction chamber. These methods also enable the production of silicon-containing compound films that are uniformly thin and continuous. These advantages, in turn, enable devices to be produced in higher yields, and also enable the production of new devices having smaller circuit dimensions and/or higher reliability.
The silicon precursor is preferably introduced into the process chamber in the form of a feed gas or as a component of a feed gas. The feed gas can include gases other than the silicon precursor, such as inert carrier gases. The carrier gas can comprise carrier gases known in the art, such as nitrogen, hydrogen, helium, argon, or various combinations thereof. Where the silicon precursor is trisilane, the trisilane is preferably introduced into the chamber by way of a bubbler used with a carrier gas to entrain trisilane vapor. More preferably, a temperature controlled bubbler is utilized.
In forming the silicon layer, deposition from a silicon precursor can be conducted according to various deposition methods known to those skilled in the art, but the greatest benefits are obtained when deposition is conducted according to the CVD methods taught herein. The disclosed methods can be practiced by employing CVD, including plasma-enhanced chemical vapor deposition (PECVD) or, more preferably, thermal CVD.
Deposition conditions are preferably tailored to processing in the particular type of reactor in which substrates are loaded. In general, deposition conditions are established to supply sufficient energy to pyrollize or decompose the silicon precursor on a hot substrate surface.
In addition, deposition conditions are preferably established so that the reaction rate of the silicon precursor is the limiting variable for the silicon deposition rate. Thus, the ability of hot wall reactors to achieve highly uniform temperature distributions can advantageously be applied to form uniform layers. While depositions conducted under reaction kinetics limited conditions have deposition rates that are sensitive to temperature changes, the ability to establish high temperature uniformity minimizes the effect of this sensitivity. Moreover, reaction kinetics limited conditions advantageously have deposition rates that are relatively insensitive to supplied reactant concentrations.
It will be appreciated that a reaction kinetics limited regime is primarily achieved by use of a relatively low temperature. This results in a reduced film deposition rate that is preferable in a batch furnace. Because of the large batch size, an adequate throughput can still be achieved at a deposition rate that results from temperatures shifted down into the reaction rate limited regime. Advantageously, trisilane enables acceptable deposition rates at very low temperatures, allowing a considerably reduced consumption of thermal budgets. As the skilled artisan will readily appreciate, thermal budgets are constantly reduced as critical dimensions are scaled down, tolerances for diffusion are reduced, and new materials with lower resistance to thermal processing are introduced. The silicon deposition process is preferably operated at a temperature below about 600° C., more preferably below about 525° C., more preferably below about 500° C., more preferably below about 475° C. The silicon can be deposited at a temperature between about 300° C. and about 500° C.
In addition to temperature, the skilled artisan will appreciate that the kinetic regime is partially dependent upon the reactant supply or partial pressure of the silicon precursor. Preferably, the reaction rate is slower than the rate at which reactant is supplied.
The thickness of the deposited silicon film can be varied according to the intended application, as known in the art, by varying the deposition time and/or gas flow rates for a given set of deposition parameters (e.g., total pressure and temperature).
A silicon layer is first deposited by flowing a silicon precursor, preferably trisilane. As noted, process conditions are preferably arranged for deposition in the kinetic regime. The process is preferably operated at a temperature below about 600° C. and, more preferably, at a temperature below about 500° C., and, even more preferably, at a temperature between about 400-450° C. In addition, the reactant supply or partial pressure of trisilane is preferably set at a sufficiently low level to maintain the deposition in the kinetic regime. As long as the reaction rate is slower than the rate at which reactant is supplied, uniformity in a properly tuned batch furnace (in which uniform temperatures can be maintained) is excellent. Reference is made to Sze, VLSI T
In addition, the silicon deposition and the TiN deposition (described above) are preferably conducted under generally isothermal conditions. In other words, if the TiN deposition is conducted at a first average temperature and the silicon deposition is conducted at a second average temperature, then the first and second temperatures differ, if at all, by preferably less than 100° C., more preferably less than 50° C., and even more preferably less than 20° C. An "average temperature" refers to a time-averaged temperature, reflecting the possibility that temperature may fluctuate during a deposition process. Conducting the silicon deposition and TiN deposition at the same or similar average temperatures simplifies processing because there is no need to significantly adjust temperature between deposition steps, or to transfer the substrates to a different reactor. In one embodiment, the TiN and silicon depositing steps are both conducted at temperatures within about 400-550° C., and more preferably within about 450-500° C.
Advantageously, the above-described in situ deposition of TiN and silicon within a relatively narrow temperature range can be conducted without producing an undesirable amount of particle generation. As described above, a chamber used for in situ processes at significantly different temperatures results in unacceptable particle generation when one of the processes is silicon deposition, due in large part to the differential in thermal expansion and contraction between the silicon and the other parts of the reaction chamber, such as the chamber walls. Silicon and TiN also have significantly different rates of thermal expansion and contraction, exacerbating the problem for adjacent TiN and silicon layers. However, the presently disclosed embodiments substantially overcome this problem, due to the relatively narrow temperature range within which the TiN and silicon layers are deposited.
The following represents process conditions in one example of in situ deposition of TiN and amorphous silicon layers onto a plurality of semiconductors in a batch reaction chamber. For pulsed CVD TiN deposition, temperature in the reaction chamber can be about 450° C., and pressure can be about 200 mTorr. The titanium precursor can be TiCl4, and the nitrogen precursor can be NH3. The TiCl4 can be delivered to the chamber via an N2 carrier gas. The flow rate of TiCl4 during the TiCl4 pulses can be about 1.5 g/min, and the flow rate of the N2 carrier gas can be about 200 sccm. The flow rate of the NH3 during deposition can be about 0.19 slm. The duration of the TiCl4 pulses can be 15 seconds, 30 seconds, or 60 seconds.
As discussed above, the TiN deposition can be conducted in three ways: (1) alternately pulsing the TiCl4 and NH3 precursors into the reaction chamber, preferably with purge or evacuation steps therebetween; (2) continuously flowing one of the precursors (such as NH3) into the reaction chamber while pulsing the other precursor (such as TiCl4); and (3) repeating the following cycle: substantially simultaneous pulses of TiCl4 and NH3, a purge or evacuation step, another NH3 pulse (also known as an "ammonia flush"), and then another purge or evacuation step. The NH3 flow during the ammonia flush can be about 1 slm.
A capping film of amorphous silicon can be deposited in situ onto the TiN layer. The temperature and pressure of the reaction chamber can be maintained at about 450° C. and about 200 mTorr, respectively. Trisilane can be continuously injected into the chamber at a flow rate of about 60 sccm, with an N2 carrier gas flow rate of about 1 slm.
Accordingly, it will be appreciated by those skilled in the art that various other omissions, additions and modifications may be made to the methods and structures described above without departing from the scope of the invention. All such modifications and changes are intended to fall within the scope of the invention, as defined by the appended claims.
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|U.S. Classification
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|Jun 19, 2007
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text:
I've held a silly hypothesis in my head ever since I was a grad student, but never had the time/resources to test it. I just recently came across a publication which drastically reduced the costs to testing the idea. It will almost certainly result in a "jokey" paper, but a fun one nonetheless.
But I could use your help. I have constructed an online survey displaying photos of people, and I need respondents to tell me whether these people are smiling, frowning or have neutral expressions. There are over 170 questions, but they are randomized, so even if you only manage to answer a few (and then close the window), it still would help a lot!
I can't tell you what the idea is just yet, because it might spoil how you answer the questions. More information to follow, once enough people have answered the survey.


text:
Black Prophecy - Behind the Scenes Part 3
Creative Director Timo Krahl and Art Director Nick Ebenhoch talk in this third installement of the Behind te scenes series about Black Prophecy's game design and graphics, their careers and personal interests.
In the beginning there is the game design document which is the operative collection of ideas and describes the overall construction of the game. Ideally this document is perfect in its first version, burned into titan plates and is then the bible of the further development process. However, this ideal case never happens and so the game design document is a small slimy and mean shapeshifter that has to be kept under control all the time. Now if you look at the "station docking" as a single feature you have to consider several factors: What kind of game am I doing? Simulation or action? Singleplayer or multiplayer? What are the technical possibilities? Which target group am I going for? How often will this feature be used? How did other developers solve this problem? Does it really benefit the game or is it just a "nice to have"?
Information aboutBlack Prophecy
SP/MP: Massive
Setting: Sci-Fi
Genre: MMORPG
Platform: PC
Release: In development


text:
I think this tea has a lot of potential if treated right. You have to find the perfect steep time because this one is not forgiving if accidentally steeped too long, it becomes very very bitter.
Overall I really enjoy this tea in the morning before class, a quick caffeine boost to start the day.
190 °F / 87 °C 4 min, 30 sec


text:
ROME, May 20 (UPI) -- Sunday's scheduled Italian Open final between Novak Djokovic and Rafael Nadal was postponed due to rain, tournament officials said in Rome.
The event was pushed forward to Monday after Maria Sharapova had defeated Li Na in the women's final earlier in the day.
That match was delayed about two hours by rain before the start of the third-set tiebreaker.


text:
Prime Minister Atal Bihari Vajpayee arrived in Gangtok on Friday on a four-day visit of Sikkim during which he will meet Chief Minister Pawan Chamling, his Cabinet colleagues and officials.
"I have been looking forward to this visit. This would enable me to see development works in the state. Sikkim has always been the centre of attraction for tourists from all over the country and I am very happy to be here," Vajpayee said.
Governor V Rama Rao and the Chief Minister received the prime minister at the helipad. Vajpayee was accompanied by his foster daughter Namita and granddaughter Niharika.
Security across Sikkim has been tightened in view of his visit. This is the first visit of the prime minister to Sikkim in nine years. Former prime minister P V Narasimha Rao had visited the state in 1994.


text:
Dear Poll: Do you Judge Books by their Covers?
Did you all watch Victoria Beckham's show on Monday night, Victoria Beckham: Coming to America? I was glued to the TV in utter amazement -- she isn't the stuck up, robotic, diva that I thought she was! Shocking I know if you didn't watch! So that got me thinking, the only reason why I put Posh in that category in the first place was because I was judging her book by its cover if you will.
I hear people say over and over again that celebrities deserve the constant scrutiny because they put themselves out there, and while I agree to an extent, sometimes we just don't know these celebrities real character traits. So ladies, do you judge Hollywood types by the person the paparazzi make them out to be?


text:
Hi Chris,
Well, this is from the person who designed the Tiny2.11:
"Hello guys,
Please, don't change the resistors : it's useless because you can easily compute the "coefficient" used in "tiny_2_1.h" and
it's dangerous because if you use a wrong value, you can DESTROY the ADC input !!!
In " #define VoltageOfAdc(adc) ( coeff *adc) " let :
* adc = raw value of the ADC input measuring battery voltage. LPC2148 are 10bits ADCs, so the raw value in software always between 0 and 2^10 (=1023)
* Vref = LPC2148 ADCs ref voltage = LPC2148 main power supply = 3.3v
* R1, R2 = resistors made up the bridge of the battery voltage measurement system (see schematic)
o R1 between Vbattery & ADC input
o R2 between ADC input & ground
The general formula to compute the coefficient is :
coeff = ( Vref / ( 2^10 - 1 ) ) x (1 + R1/R2)
coeff = ( 3.3 / ( 1024 - 1 ) ) x (1 + R1/R2)
coeff = 0,0032258 x (1 + R1/R2)
For example :
Tiny 1.1 : R7 = 15k, R15 = 3.3k => coeff = 0,0178885630
Tiny 2.1 : R1 = 15k, R2 = 3.3k => coeff = 0,0178885630
Tiny 2.11 : R1 = 10k, R2 = 1.5k => coeff = 0,0247311828
But, it's an approximate value because of the dispersions of the components :
* resistors values (+/-1% or 5%)
* power supply (not exactly 3.3v)
* etc."
I'm at a loss what is all means specifically but in layman's terms I think it's just related to the volage on the pins on the ADC connectors. So if you have a 3.3v Gyro or sensor you want to be sure you have the correct resistor for R2 (actually none 0k). If you have a 5v Gyro you want the right resistor for that (1.8k)...by using the "default" I can use a 5v Gyro on the ADC without having to do that "resistor bridge" modification described on the Wiki. I kinda like that.
Honestly, I'd like a more simple explanation. No math just what does it mean . That you'll see a lower voltage in the GUI display? It will burst into flames mid-flight? Somewhere in between?
Last edited by bmw330i; May 30, 2008 at 11:27 PM.
Hi David.
I also computed the coefficient in my previous post and actually your post and my post say the same things.
It is very simple actually.
Since the adc has 10 bits(my mistake on my previous post, i meant 10 bits not 12) then it can count up to 1024 different voltage levels 0 included.
(I intensionally used 1024 not 1023 to avoid confusion)
The adc when it measures the voltage it compares it with its internal reference which is 3.3 volt in our case.
If the input voltage is say 3.3/2= 1.65v the adc will count 511, if it is 3.3v it will count 1023, if it is 3.2mv will count 1 and in other words each count of the adc counter corresponds
to 3.3Volt / 1023 ~= 3.2 mv
The adc input voltage cannot be more than the reference voltage because the adc cannot count more than 1023 and a bigger input voltage will burn the adc input.
That's where the resistor divider come in.
If we don't use a resistor divider we can only measure up to 3.3 volts and a higher voltage not only cannot be counted but it will burn the adc input and probably the whole adc.
With a resistor divider we can measure higher than 3.3 volts but we have to make sure that the voltage at the adc input pin (at the chip) will never exceed 3.3 volts by selecting a division ratio high enough that the output of the voltage divider with the max expected input will never exceed 3.3 volts
For example a 5v gyro will be able to vary its output voltage from 0 to 5 volts
but 5 volts at the adc input pin is not acceptable so we have to use a voltage divider with a division ratio of 5/3.3=1.5151515 or higher thus
We choose R2 first and then we compute R1 and if the value of R1 is not commercially available we choose the next higher value R1 and recalculate the
division ratio or we choose a different R2 so we can find close enough
commercially available resistor values and recalculate.
The value of R1+R2 should be high enough not to load the source's (Gyro output) internal resistance much which should be given from the Gyro manufacturer's datasheet (usually a R2 between 1 and 10 Kohm is acceptable).
The Gyro datasheet should state something like "max output voltage @ 1Kohm"
or state at which load resistance the output voltage was measured or calibrated. This resistance is the value of R1+R2.
With the use of a voltage divider at the adc input, each adc count will represent
3.2mv * the voltage division ratio which is R1/R2 + 1.
R1 is the resistor of the voltage divide that is connected to the + side and R2 is the resistor that is grounded.
Finally we have that each adc count will represent a voltage at
the resistor divider input of:
3.3v / 1023 multipled by R1/R2 +1 and the result is the adc coefficient.
Last edited by hendrix; May 31, 2008 at 05:17 AM.
...lol...that's awesome. Really. You did try. But that's still a lot of Math. Not that it's past me. I just am missing the black and white part of this.
My immediate issue is: Does something need to change with the Tiny2.11 to correct using the default resistors or not? If so I wish someone would correct it and post the new values to the Wiki.
When I send the parts to get them assembled I make no modifications. Whatever the Wiki and design states is what gets assembled. So, if the design has a flaw so will the finished assemblies. Our company simply provides the service of taking the design and having it assembled. So, I'm concerned not for just me but everyone.
Please, no Math. Just does the design need to be modified or no? If so please email the list so the designer can modify his design.
No David don't worry, you don't need to change anything since we can tweak the coefficient in tiny_2_1.h and get the correct result.
It works very well this way so you don't need to change anything.
I am very pleased by the quality of the tiny 2.11 board and i find it very reliable.
At last there is an autopilot that works and it doesn't cost a fortune...
Of course this is my opinion.
Last edited by hendrix; Jun 01, 2008 at 01:36 AM.
Ok, cool, thanks. I know how to do that edit to the library file. I will post the specific edit for my project when I get around to editing it. Would be interesting if everyone posted their value so we could see the range of values. Maybe there is a "default" value that could be used.
Well, today is Sunday and I vowed to get some building done. I need to take some new photos as well of the FunJet as it is. I'll do that then post up an update.
I owe this thread an update. I spent the last week simply trying to get the next order for 100 of the Tiny2.11 placed.
The whole reason for my opening a business was to help people get Paparazzi hardware so that takes a priority to my own Hobby/Build of our Funjet. Soon as everyone is taken care of then I get back to the build. Just want to make sure everyone gets treated like I would want to be treated.
Tomorrow AM I promise to take the FunJet out and snap some photos though. I'm also notified that the LEA_5H may not work with the default Paparazzi code so I'm looking into that. The LEA-5H is so sensitive it gets a fix indoors before I even put the antenna on...for comparison an LEA-4P will not get a fix even with an antenna. So, I'd like to only use the LEA-5H if possible...so tracking down that info now. I will update as I learn about this.
More on the LEA-5H
I did a "grep" for POSLLH in the code...I found only one file with reference to it: gps_ubx.c
I belive this is the code:
void parse_gps_msg( void ) { if (ubx_class == UBX_NAV_ID) { if (ubx_id == UBX_NAV_STATUS_ID) { gps_mode = UBX_NAV_STATUS_GPSfix(ubx_msg_buf); #ifdef GPS_USE_LATLONG /* Computes from (lat, long) in the referenced UTM zone */ } else if (ubx_id == UBX_NAV_POSLLH_ID) { gps_lat = UBX_NAV_POSLLH_LAT(ubx_msg_buf); gps_lon = UBX_NAV_POSLLH_LON(ubx_msg_buf); latlong_utm_of(RadOfDeg(gps_lat/1e7), RadOfDeg(gps_lon/1e7), nav_utm_zone0); gps_utm_east = latlong_utm_x * 100; gps_utm_north = latlong_utm_y * 100; gps_alt = UBX_NAV_POSLLH_HMSL(ubx_msg_buf) / 10; gps_utm_zone = nav_utm_zone0; #else } else if (ubx_id == UBX_NAV_POSUTM_ID) { gps_utm_east = UBX_NAV_POSUTM_EAST(ubx_msg_buf); gps_utm_north = UBX_NAV_POSUTM_NORTH(ubx_msg_buf); uint8_t hem = UBX_NAV_POSUTM_HEM(ubx_msg_buf); if (hem == UTM_HEM_SOUTH) gps_utm_north -= 1000000000; /* Subtract false northing: -10000km */ gps_alt = UBX_NAV_POSUTM_ALT(ubx_msg_buf); gps_utm_zone = UBX_NAV_POSUTM_ZONE(ubx_msg_buf); #endif
I will try enabling it myself...as always will report what I find.
Code option
The code appears to check for the ID string of the GPS data stream. Once you find the version of data stream, and / or set the LEA-5H to a specific data string format permanently, it appears that much of that whole subroutine could be eliminated.
To maintain compatibility across multiple GPS data types this appears to identify the type of data string and then return the results of parsing that string. ( or set the values up in variables that are used elsewhere.) If it was mine I would lock the GPS in a specific mode and delete all the code that references alternate data string types. I am not keen on redundant code that does not get accessed.
Possibly a header file or compile time option could be used to specify the GPS type so only the code for the specific data string parsing would be compiled into the finished code. Doing this throughout the code for various options such as FMA co-pilot Yes or No, and other optional components could make smaller and tighter executable.
Just a consideration.
Jim H
I suppose I need to just pug in an XBee Module, fire up GPS and see what shows in the display don't I? Ok, I have an LEA-5H Tiny2.11 now in the shop...I have some new v2 (200mW) XBeePro modules I need to test out anyhow...
Now if GCS shows GPS info then can I assume it does work? Is there some other test(s) to run?
For Papa Project: the more hardware availability, the better, mature & stronger this development will go, If you agree with me.
I will try to put contribution rather, links ! ok
Nice talking to you! have a rewarding day!
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