Tempress Systems TS-6303 User manual

Furnace Reference Manual
Tempress Systems Inc.
Furnace manual
M320_01 January 2004

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TABLE OF CONTENTS
Table of contents
1. Introduction .......................................................... 1-1
1.1 Scope of the manual ................................................................. 1-1
1.2 Furnace models ........................................................................ 1-1
2. Description ........................................................... 2-1
2.1 Diffusion system........................................................................ 2-1
2.2 Components of the furnace....................................................... 2-3
2.3 Furnace cabinet ........................................................................ 2-4
2.4 Scavenger................................................................................. 2-4
2.4.1 Available models........................................................ 2-4
2.4.2 Description of the Scavenger..................................... 2-4
2.5 Cooling unit............................................................................... 2-5
2.6 Fast Cooldown.......................................................................... 2-6
2.7 Heating elements (disposacore) ............................................... 2-7
2.7.1 Tube heating module ................................................. 2-7
2.7.2 Heating elements, tube adapters, isolation collars .... 2-8
2.8 Support and sealing ................................................................ 2-10
2.9 Furnace temperature control................................................... 2-11
3. Installation ............................................................ 3-1
3.1 Introduction ............................................................................... 3-1
3.2 Unpacking................................................................................. 3-1
3.3 Installation................................................................................. 3-2
3.4 The furnace............................................................................... 3-2
3.5 The scavenger .......................................................................... 3-3
3.6 Inspection ................................................................................. 3-3
4. Start-up ................................................................. 4-1
4.1 Introduction ............................................................................... 4-1
4.2 Start-up ..................................................................................... 4-1
4.3 Fast Cooldown.......................................................................... 4-3
4.4 Burn-in and Oxidation of an Heating element ........................... 4-3
FURNACE REFERENCE MANUAL I

TABLE OF CONTENTS
4.5 Installation of the Quartz Tube.................................................. 4-5
4.6 Test and Calibration Procedure ................................................ 4-6
4.7 Pre-Cleaning of the Process Tube............................................ 4-6
4.8 Automatic profiling procedure ................................................... 4-8
4.8.1 Automatic profiling procedure .................................... 4-8
4.8.1.1 Introduction to profiling................................ 4-8
4.8.1.2 Profiling recipe setup................................... 4-9
4.8.2 automatic profiling preparation ................................ 4-11
4.8.3 Paddle TC installation.............................................. 4-11
4.8.3.1 Profile recipe selection .............................. 4-12
4.8.4 Automatic profiling RUN .......................................... 4-12
4.8.5 Summary automatic profiling ................................... 4-13
5. Maintenance ......................................................... 5-1
5.1 Introduction ............................................................................... 5-1
5.2 Heating Element Coil ................................................................ 5-1
5.3 Heating elements...................................................................... 5-3
5.4 The SCR-Module ...................................................................... 5-3
5.5 Heat Exchanger ........................................................................ 5-4
5.6 Tube change............................................................................. 5-5
5.7 Tube change diffusion system tubes......................................... 5-5
5.8 Tube change LPCVD and vacuum system tubes ..................... 5-6
5.9 Preventive Maintenance ........................................................... 5-7
6. Calibration/Adjustments ..................................... 6-1
7. Trouble Shooting ................................................. 7-1
FURNACE REFERENCE MANUAL II

LIST OF FIGURES
List of figures
Figure 2-1 Outline drawing of a Furnace System, model TS6804.......... 2-2
Figure 2-2 Round scavenger box layout (Diffusion) ............................... 2-5
Figure 2-3 Cooling unit........................................................................... 2-5
Figure 2-4 Fast Cooldown principle........................................................ 2-6
Figure 2-5 Heating element for diffusion furnaces.................................. 2-8
Figure 2-6 Tube adaptors, support and radiation heat shield ............... 2-10
Figure 2-7 Zone paddle profiling thermocouple.................................... 2-11
Figure 2-8 Double spike thermocouple................................................. 2-11
Figure 4-1: Spike thermocouple .............................................................. 4-2
Figure 4-2: Tube adapter......................................................................... 4-2
Figure 4-3: Position of the thermocouple................................................. 4-5
Figure 5-1 The heating element adjustment............................................ 5-2
FURNACE REFERENCE MANUAL III

INTRODUCTION
1.Introduction
1.1 Scope of the manual
The contents of this manual and drawings are to provide the necessary instructions and
information for installing, adjustment, operating, maintenance and understanding of the
Amtech/Tempress Systems Furnace. Before starting up, installing, operating and/or
maintaining the system, read this manual first.
1.2 Furnace models
This manual is meant for the following Tempress Diffusion models:
Model number Wafersize
Capability
Nr of tubes Flat-zone length
TS-6300 series
TS-6303
TS-6304 150 mm
3
4
25-30 cm
(12 inch)
TS-6600 series
TS-6603
TS-6604
150 mm
3
4
55-60 cm
(24 inch)
TS-6800 series
TS-6803
TS-6804
150 mm
3
4
75-80 cm
(32 inch)
TS-61000 series
TS-61003
TS-61004
150 mm
3
4
95-100 cm
(40 inch)
TS-8600 series
TS-8603
TS-8604
200 mm
3
4
55-60 cm
(24 inch)
TS-81000 series
TS-81003
TS-81004
200 mm
3
4
95-100 cm
(40 inch)
TS-12800 series
TS-12803
TS-12804
300 mm
2
3
75-80
(32 inch)
Table 1 Different types of furnace models
FURNACE REFERENCE MANUAL 1-1

INTRODUCTION
The TS-6000 series
The TS-6000 series is a line of horizontal furnaces for up to 150 mm. (6 inch) wafers. This
system is standard equipped with an accurate 3 zone digital controller for optimum
temperature control.
In this line the following models are available:
•TS-6300 series: Designed for 150 mm R&D institutes. With its flatzone of 30 cm,
loads of 25 to 50 wafers can be processed.
•TS-6600 series: Designed for small batch or pilot production, 150 mm facilities.
With its flatzone of 60 cm, loads of 50 to 100 wafers can be
processed.
•TS-6800 series: Designed for 150 mm production facilities. With its flatzone of 80
cm, loads of 100 to 200 wafers can be processed.
•TS-61000 series: Designed for high volume, 150 mm production facilities. With its
flatzone of 100 cm, loads of 150 to 300 wafers can be processed.
The TS-8000 series
The TS-8000 series is a line of horizontal furnaces for up to 200 mm. (8 inch) wafers. These
systems are equipped with an accurate 5 zone digital controller for optimum temperature
control.
In this line the following models are available:
• TS-8600 series: Designed for small batch or pilot production, 200 mm facilities.
With its flatzone of 60 cm, loads of 50 to 100 wafers can be
processed
•TS-81000 series: Designed for high volume production, 200 mm facilities. With its
flatzone of 100 cm, loads of 100 to 200 wafers can be processed.
The TS-12800 series
The TS-12800 series is a line of horizontal furnaces for up to 300 mm. (12 inch) wafers.
These systems are equipped with an accurate 5 zone digital controller for optimum
temperature control.
In this line the following models is available:
• TS-12800 series: Designed for high volume production, 300 mm facilities. With its
flatzone of 80 cm, loads of 100 to 150 wafers can be processed.
FURNACE REFERENCE MANUAL 1-2

DESCRIPTION
2.Description
2.1 Diffusion system
The Furnace is designed to perform Diffusion/Atmospheric and Low Pressure Chemical
Vapor Deposition (LPCVD) processing on wafers from 75 mm up to 300 mm, and may be
installed in a cleanroom environment.
The furnace is housed in a utilized cabinet of heavy gauge metal construction with a Clean
Room Compatible Polyurethane finish. It contains max. 4 heating elements. Within the
furnace the heating elements are numbered from 1 to 4, starting with tube number 1 at the
top. The heat exchanger on the top of the furnace cools the exhausted air (a water-cooled
mantle for each tube is available as an option). Three phase power transformers are used to
maintain a constant temperature with a minimum of disturbance on the mainpower
distribution system.
The integrated modular construction provides discrete compartments for control equipment.
All electrical wiring, including the basic units of the temperature controller and electrical
components are housed in the base of the furnace.
The diffusion system may have a right or left handed orientation to suit the customers needs
(furnace on the right when standing in front of the loadstation means a right-handed system).
Major components of the diffusion system are:
•Load Station
•Furnace System
•Cross flow box (Horizontal or Vertical Flow Loadstation)
•Gas Cabinet
•Control system
On the next page an outline drawing of a Furnace System, model TS6804 is shown:
FURNACE REFERENCE MANUAL 2-1

DESCRIPTION
Figure 2-1 Outline drawing of a Furnace System, model TS6804
FURNACE REFERENCE MANUAL 2-2

DESCRIPTION
A: top view of the furnace with scavenger
1: Water outlet Bulkhead Swagelok (furnace cooling)
2: Water inlet Bulkhead Swagelok (furnace cooling)
3: Exhaust Furnace
4: Water outlet Bulkhead Swagelok (cooling vacuum-flanges)
5: Water inlet Bulkhead Swagelok (cooling vacuum-flanges)
6: Exhaust scavenger-box
7: Exhaust scavenger-housing
B: sideview of the furnace
C: frontview of the furnace
8: Scavenger box exhaust.
9: Tube switch
10: Key switch control power on-off
11: Mainswitch (lockable in off-position)
12: Mainpowerconnection
13: Excess Temperature Controller
D: view of the loadside of the furnace
8: Scavenger-box exhaust
E: rearside of the furnace
8: Scavenger-box exhaust
2.2 Components of the furnace
• Furnace cabinet
• Scavenger
• Cooling unit
• Fast Cool down
• Heating elements
• Tube (support and sealing)
• Flange
• Furnace Temperature Control
• Power supply
• Main switch assembly
FURNACE REFERENCE MANUAL 2-3

DESCRIPTION
2.3 Furnace cabinet
The furnace is housed in a utilized cabinet of heavy gauge metal construction with a Clean
Room Compatible Polyurethane finish. (See Figure 2-1).
•Optional: Cabinet over-temperature protection sensor on top of the cabinet.
2.4 Scavenger
All 3-stack and 4-stack furnaces are provided with a toxic gas scavenger. Depending on the
application, with or without a front door.
2.4.1 Available models
A) Stainless steel round box with adjustable outlet in the box and one exhaust pipe with
outlet on the top of the furnace on which all boxes are connected. Normally used for
OMEGA-Juniors and all one-stack furnaces.
B) Same as A, however with the provision that service now can be done from the
maintenance room. Each box provided with a separate outlet to the top of the furnace
with adjustable valve. All outlets on the top connected to a manifold. Used for furnaces
with automatically boatloading, cantilever systems etc.
2.4.2 Description of the Scavenger
•Sealing between clean room and service room.
•One exhaust connection on top, there is however also an exhaust connection
possible on the bottom (optional).
•Door for maintenance on the service side.
•Stainless steel round scavengers.
•Each compartment is exhausted and adjustable independently.
•Each compartment has an individual monitor for the scavenger pressure (optional).
FURNACE REFERENCE MANUAL 2-4

DESCRIPTION
Figure 2-2 Round scavenger box layout (Diffusion)
2.5 Cooling unit
The cooling module is mounted on the top of the furnace. It is a water/air heat exchanger,
with high-efficiency aluminium fins, for optimised surface area. The water quantity
(preferably soft water) is 3-7 l/min, depending on the inlet water temperature. (see Figure 2-1
and Figure 2-3) The electrical fans on top of the module extract the hot air through the
radiator fins and cooled air is blown-out in the room again. The fans start running, as soon as
the main switch of the furnace is switched on.
Figure 2-3 Cooling unit
FURNACE REFERENCE MANUAL 2-5

DESCRIPTION
2.6 Fast Cooldown
Air is forced by a blower to travel between the heating element mantle and the outside of the
process tube. The direction of airflow is alternated to achieve balanced cooling faster than
the conventional furnace.
The air used for cooling is re-circulated. It is cooled by a water-cooled heat exchanger built
in, in the furnace cabinet.
The blower is a centrifugal type. The speed is controlled by the DTC and is varied according
to requirements. The blower is connected to the heat exchanger and heating element via
tubing. The Cool down modules (blower and heat exchanger) are both situated behind the
heating elements.
Cooling Process
Cool down is assisted by conditioned air that is forced to flow between the heating element
and the process tube (Figure 2-4). The flow of air is periodically reversed left-to-right; right-
to-left to equalize out the cooling effect over the whole wafer load. During cool-down, only
paddle thermocouples are used for temperature measurement. The flowing past the spike
thermocouples makes their use inaccurate.
Figure 2-4 Fast Cooldown principle
Control of the valves and blower during cool-down is done by the DTC which has dedicated
software for the purpose. The cool rate in the temperature table determines the cool down
time and the DTC attempts to maintain this rate over all zones.
FURNACE REFERENCE MANUAL 2-6

DESCRIPTION
At the start of the cool-down step, the DTC checks the current temperature setpoint, the
paddle setpoint (target temperature) and the ramp (slope) to see if forced cooling is
necessary. If it is, the DTC calculates a profile (temperature over time) required to reach the
target setpoint, and sets the blower speed to an appropriate value (determined by an
algorithm). While cooling is in progress, the DTC applies power to the element end zone to
maintain an even cooling “ramp” and to maintain a flat zone.
When the system reaches the paddle setpoint, the blower is ramped down and turned off. At
this point the DTC switches automatically back to cascade control.
2.7 Heating elements (disposacore)
•The furnace contains 3 or 5 zone heating elements of the standard Tempress
Systems specification and are used for optimum temperature characteristics.
•The furnace can contain any of the following heating elements: a multipurpose
Kanthal A-1 coil, a high temp APM coil, an ultra high temp Kanthal Superthal®coil,
Low temp white John, MRL heating elements or light Gauge for high/low
temperature applications. Insulation made from high purity, high density, vacuum
molded alumina silica fiber (optional light Gauge). It depends on the process
temperature, which kind of element is used. Custom desired other elements can be
implemented on request.
•Over temperature protection is provided by an Excess Temperature Controller,
connected to separate Thermocouples. See section Error! Reference source not
found.
•Each heating element has its own transformer with isolated coils powering individual
control zones via high-efficiency zero-crossover fired Silicon Control Rectifier (SCR)
power control modules.
•One tube switch per heating element, to shut off one tube only.
•Tube sizes depending on customer demand.
•The combination of the special coil-design, insulation, stainless steel shell and the
DTC guarantees:
•better uniformity
•long lifetime
•energy saving
•no element sagging
2.7.1 Tube heating module
This module, most of the times multi-zone, consists of a Fibrothal®heating element with
embedded Kanthal alloys and a stainless steel mantle. This module is meant for diffusion
furnaces. See Figure 2-5.
The advantages of this construction are:
•High temperature equability
•Exact temperature profile
FURNACE REFERENCE MANUAL 2-7

DESCRIPTION
•High operating capacity
CONNECTOR FO
R
POWE
R
STAINLESS STEEL MANTLE
Figure 2-5 Heating element for diffusion furnaces
Life-time and maximum temperature
The typical lifetime of a heating element is 5-15 years but is highly dependent on many
factors. Strong temperature fluctuation and high temperature may reduce the actual lifetime.
Note: Keep in maximum recommended temperature, overshoot will highly increase
the ageing of the heating element.
2.7.2 Heating elements, tube adapters, isolation collars
Kanthal heating elements are isolated with ceramic fiber material. If the material is disturbed,
fibrous dust may be generated. This dust may be carcinogenic.
DANGER
If the temperature exceeds 900°C, silcogene chemicals such
as Kristobalite may be formed. Use appropriate safety
measures. See Material Safety Data Sheet.
General Precautions
• Read the Material Safety Data Sheet and follow the advice and procedures they
contain.
FURNACE REFERENCE MANUAL 2-8

DESCRIPTION
• Wear protective clothing and equipment appropriate for the hazard, this include
overall, hat, dust mask (with a particulate air filter cartridge to DIN 3181 P3),
goggles and gloves.
• Reduce underfoot debris, keep the work area clean.
• Use a vacuum cleaner with a HEPA filter.
• Work in a controlled and careful manner to avoid dust generation and dispersion
Handling
• Never saw, cut or sand silicate fiber material.
• Double-bag, seal and label heating elements for transport.
• Treat heating elements and silicate fiber as chemical waste.
Chemical properties
The ceramic fiber modules contain a high chemical resistance except liquid acids, phosphoric
acids and strong bases. Moistening with water or oil doesn’t influence the properties of
ceramic fiber itself. After drying respectively evaporation, the thermal and physical properties
will be set to their normal conditions.
Be careful with the material in combination with heating elements, because of possible
corrosion
Safety prescriptions
Health Inhalation can cause health injuries. Avoid contact with skin or
eyes.
First aid In case of contacting with skin or eyes: don’t rub, but flush
immediately with ample water.
Protection measures air-exhaust, Dust-mask P2, Goggle and Working clothes with long
sleeves
Labor hygiene wash unprotected skin surfaces thoroughly with water.
Gather working clothes separate.
FURNACE REFERENCE MANUAL 2-9

DESCRIPTION
2.8 Support and sealing
•Tubes may be supported by tube supports and centered by tube adapters. The use of
tube supports for high temperature elements is not recommended.
•Radiation heat shield (1 per tube), made of Moldatherm®insulation plate and
covered with an aluminium or stainless steel cover.
•Tight sealing between tube and scavenger (optional).
Figure 2-6 Tube adaptors, support and radiation heat shield
FURNACE REFERENCE MANUAL 2-10

DESCRIPTION
2.9 Furnace temperature control
•The Digital Temperature Controller provides master/slave or independent zone
control. It features proportional, integral and derivative (PID) temperature control
functions.
•Digital Temperature Controller, with 3 to 5 zone spike (optional) and paddle control
per tube. Ramping, limit alarms, TC break and power failure alarms and 4
temperature recipes.
•Thermal flatzone is depending on the type of furnace.
•Double spike thermocouples, one for temperature control and one for the Excess
Temperature protection.
•Tripple thermocouples, two are for the spike control (in case of failure of one) and
the third one is for the Excess Temperature protection.
•Optional other control system, see separate manuals.
•Thermocouple connections on source or load side of the furnace, for Paddle control
and profiling. See Figure 2-7 and Figure 2-8:
Figure 2-7 Zone paddle profiling thermocouple
Figure 2-8 Double spike thermocouple
FURNACE REFERENCE MANUAL 2-11

INSTALLATION
3.Installation
3.1 Introduction
In this chapter contains a detailed description about the unpacking, installation and
inspection procedures. When the furnace is moved in transit and during final placement at
the customer's facility, care should be exercised at all times.
CAUTION
Transport of the system should be in an upright position
at all times.
3.2 Unpacking
•Before the furnace is unpacked, a visual inspection of packing materials should be
made. If there is evidence of damage during transport, the carrier should be
contacted so that an inspector can be present to verify any damage before the
furnace is unpacked.
•If there is any visible damage, notify Amtech/Tempress Systems verbally and in
writing. This must be done within 24 hours, after arrival of the shipment.
•A forklift truck, with a minimum capacity of 1500 kg, is recommended to be
available to move/carry the furnace in its right place.
CAUTION
The furnace is packed in 2 layers of plastic. The first layer
must be removed outside the clean room. The second
layer must be removed in the clean room.
Unpacking:
•Check off all boxes against the packing list.
•Unpack the boxes one by one.
•Check the contents of the boxes against the collo contents list
•If any damage is visible, then....
CAUTION
Do not dispose any of the packing materials or boxes.
•Release and remove equipment wrappings.
FURNACE REFERENCE MANUAL 3-1

INSTALLATION
CAUTION
Lift or pull the wrappings away from all stainless steel
surfaces. Do not drag packing materials across the
equipment surfaces as this may cause damage.
•Depending what type of packing material is being used; a final de-dusting must be
done before it is put into position. The system has been pre-cleaned before leaving
our factory.
3.3 Installation
CAUTION
During movement, the furnace assembly is slightly
unstable and should be considered top heavy.
3.4 The furnace
CAUTION
Items, described in this paragraph, are the customer's
responsibility.
•Check the bottom side of the furnace for levelers and sagged wires.
•To prevent moving of the furnace during perpendicular lift up, use wooden packing
block.
•Locate the furnace in its final position.
CAUTION
T
he tines of the forklift should extend under complete
width of the furnace when moving.
•Place a spirit-level on top of the furnace. The furnace can then be leveled, by
adjusting the adjustable feet on the bottom of the furnace.
•Locate the loadstation and the gascabinet in their position.
•Level and align the loadstation and the gascabinet with respect to the furnace.
•Install all facilities as indicated on the outline drawing and verify that they comply
with the labeling.
FURNACE REFERENCE MANUAL 3-2