centrotherm international AG

The centrotherm c.ACTIVATOR has been developed for high-temperature annealing applications in high-volume SiC device manufacturing but it is also ideally suited for other materials. There are two versions available providing wafer size capabilities up to 200 mm. The unique all metal free design of the centrotherm process tube and heating system allows process temperatures up to 2000 °C.

The main application for c.ACTIVATOR is the electrical activation by post implantation annealing for SiC MOSFET and diode manufacturing at high temperatures of up to 2000°C.

Further applications are

• High-temperature hydrogen annealing to smooth, clean and round trenches after (RIE) etching in order to improve channel mobility and reduce field crowding on sharp corners in trench MOSFET manufacturing
• Cost-efficient dopant activation in GaN wafers at 1150 - 1250°C
• Annealing of AlN seed layers and AlN epitaxial layers at ~1700°C

Processes

• SiC annealing
• Post implantation annealing
• H2 annealing for trench optimization
• GaN annealing
• AlN annealing

Options

• Load lock - mini environment with N2 purge option for up to 25% throughput enhancement
• Vacuum processing < 10-3 mbar
• Automated wafer handling system
• Higher throughput > 100,000 wafers/year (depending on process)

The centrotherm c.OXIDATOR high-temperature oxidation furnace has been developed for the special needs of SiC oxidation but can also be used for silicon oxidation. The high-volume furnace is available in two versions allowing wafer sizes up to 200 mm. Optionally c.OXIDATOR supports in-situ wet oxidation as well as H2 and NH3 annealing applications.

Temperatures up to 1500 °C and all other supported features open up a wide range of possibilities to SiC oxidation and the development of an oxide layer with low interface trap density (Dit) and high channel mobility.

The outstanding reactor has been designed for high performance, small footprint and low cost of ownership while offering highest process flexibility.

The tube and the heating element inside the vacuum reactor chamber are designed for a safe use of toxic and flammable gases.

Post-oxidation annealing (POA) in NO, N2O or NH3 atmosphere leads to improved SiO2/SiC interface and thus higher channel mobility as well as improved stability and lifetime of the oxide on SiC.

H2 and H2O (O2-/ H2-rich) are available for pre- and post-treatment of thermal and deposited gate oxides.

Thanks to the corrosion resistant design, chlorine provided by a DCE bubbler can also be safely used without long-term damage to the door seal and exhaust line. Chlorine can be used to clean the SiC process equipment as well as for the process itself.

Due to its vacuum capability, c.OXIDATOR can be excellently used in the development, optimization and production of high quality thermal gate oxides, as well as for a variety of pre- and post-treatments, which are also essential for deposited oxides. 

Processes

• High-temperature SiC and Si oxidation
• POA (Post oxidation annealing) in NO, N2O or NH3 atmosphere
• Wet oxidation
• High-temperature H2 substrate pre-treatment

Options

• Hydrox for wet oxidation
• Automated wafer handling system

The stand-alone RTP system c.RAPID 200 has been especially developed for multiple process requirements in R&D and production lines. High performance and flexibility combined with low cost of ownership make it the best choice in rapid thermal processing.

The capability to run a substrate on a susceptor or within a box in combination with atmospheric or vacuum operation enables a wide range of possible applications for compound semiconductors (e.g. for SiC or GaN).

Its wafer surface-independent temperature controllability is unique among all existing RTP solutions. The pyrometer-based temperature measurement system enables processes at low and high temperatures. Independent lamp control combined with predictive PID control provides excellent thermal accuracy and repeatability.

c.RAPID 200 operates with a fully automatic loading system and is available as single or dual chamber version and with up to 4 cassette stations.

Processes

• Rapid Thermal Annealing (RTA)
  • Ion implant annealing
  • Contact/metal anneal
  • Source/drain anneal
• Silicide formation (Ti, Co, Ni, Pt, etc.)
• PSG reflow
• Dopant activation

The centrotherm c.HORICOO 200 is a field-proven and ultra-versatile tube furnace system that is available for mass and medium volume production as well as for Research and Development.

It provides reliable process capabilities and high process performance for multiple applications, such as atmospheric and low pressure diffusion as well as LPCVD processes. The process tubes can be configured for various processes with associated facilities. Within one furnace atmospheric, LPCVD or mixed-tube configuration can be installed.

All furnaces can be equipped with an integrated boat handling system as well as an integrated wafer transfer system. Interference between individual tubes is minimized by water-cooled heating cassettes. The softlanding system enables repeatable wafer positioning within the tube, independent from wafer load. Ease of maintenance ensures low cost of ownership and a high uptime.

Atmospheric processes

• Wet and dry oxidation (DCE, HCl)
• Diffusion (e.g. POCl3, BBr3)
• Annealing (H2, N2)
• Activation annealing
• Contact sintering
• Curing
• Nitridation
• Silicidation

LPCVD processes

• Polysilicon and amorphous silicon
• Doped Polysilicon
• Silicon Nitride
• Low stress Nitride
• TEOS | PSG | BPSG
• LTO | HTO
• Oxynitride
• SIPOS

Special processes

• Low-pressure diffusion (POCl3)
• Gallium diffusion
• Aluminum pre-deposition/diffusion

Options

• Boat elevator and boat storages
• Integrated full automatic wafer transfer system
• Flowbox

The centrotherm c.HORICOO 300 horizontal batch-type system is designed for 300 mm wafer processing with reliable performance in mass production. Based on centrotherm‘s extensive expertise in the semiconductor industry, c.HORICOO 300 is the new high-throughput platform for state-of-the-art wafer processing.

The heating element comprises 5 heating zones where each zone consits of two half shells that proved excellent temperature uniformity. The centrotherm Hydrox system supports wet oxidation processes with different moisture levels.

Temperatures up to 1200 °C allow faster oxidation and shorter drive-in processes.

The system is equipped with a modern touch operating HMI and factory-host coupling for MES connection. The latest CESAR II software enables a SEMI-compliant recipe management as well as remote control and maintenance.

The modular concept of c.HORICOO 300 also allows a single furnace 4-stack version or a cluster version with up to 8 tubes.

Processes

• Wet and dry oxidation (DCE or HCl)
• Annealing (N2)

Options

• 4-stack single-furnace version

To optimize the yield for wide band gap (WBG) materials and semiconductor devices, stress-related defects and dislocations must be kept to a minimum. A method to reduce yield loss related to defects and dislocations is by thermal treatment of the crystals immediately after the growth process.

The high-temperature annealing furnace c.CRYSCOO HTA has especially been developed to significantly improve productivity and cost of ownership along the WBG materials and device value chain.

Due to its superior temperature control and uniformity c.CRYSCOO HTA outclasses conventional furnaces. The large process chamber allows the processing of over 12 boules, ingots or even 100 raw wafers simultaneously. This capacity in combination with a superior temperature homogeneity results in a higher yield per crystal.

Processes

• Post-growth annealing of WBG crystals (boules, ingots, raw wafers)
• SiC powder manufacturing (process steps, incl. purification)
• GaO/GaN-on-SiC (material optimization)
• AlN on sapphire or SiC (lattice mismatch)