RF Plasma Sources RF 50/63

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1 RF Plasma Sources RF 50/63 n Largest range of models : from research to production n High atomic species production n Perfect for spintronics and high-k gate for continuous Moore s law n Perfect for MgZnO and related oxides : future electronics n Perfect for GaN based LED and Power Amplifiers n Amazing GaN growth rate achieved with RF-N 50/63 up to 2.5µm/h n Optical detector directly attached to inspection viewport n for an excellent control of the growth rate Riber offers the largest range of RF sources on the market. RF source models cover the needs from research to production machines. Different materials for the discharge cavity are available to configure the source for the generation of atomic nitrogen, oxygen or hydrogen. RF sources are used for a wide range of applications such as nitrides (GaInAlN,etc.), diluted nitride (GaInAsN, II-VI doping), oxides (ZnO, spintronics, high-k, etc.), diluted oxides (doping, mixed nitride / oxide) and in-situ hydrogen surface cleaning. The Riber RF source uses MHz high brightness plasma to produce an atomic species beam from a gas. An innovative RF cavity/coil coupling is used to obtain the highest atomic species production efficiency on the market for RF plasma sources. The design allows the cavity to be maintained at a high temperature to minimize unwanted energy ion extraction. An innovative LC circuit makes tuning easier than ever before. Active atoms are injected into the growth chamber through a series of small holes at the end of RF cavity. The number of holes can be optimized for particular applications. For example a small N atom flux is easily achieved for GaAsN growth by adding a low flux diaphragm. The resulting flux density permits (for example) the growth of GaN at rates in exceeding several µm per hour. The RF source atom fluxes are higher than atoms/cm²/s for10 cm working distance.

2 WORKING PRINCIPLES The RF plasma source operates by means of an electrical field produced by the inductive coupling of the RF coil surrounding a cavity. An RF (13.56 MHz) generator delivers the power to the discharge cavity space. To maximize the transfer of power to the plasma a matching network is used to match the 50 Ohm impedance of the generator to the purely 50 Ohm impedance of the cavity load. By adjusting the network capacitors, standing waves are avoided and the transfer of power from the generator to the plasma is maximized (during these conditions a minimum of power reflection is observed). The plasma in the cavity space produces atoms by dissociation of the molecular species. The atoms escape along with the nondissociated molecules into the vacuum environment through an array of small holes in the front disk of the cavity («end plate»). The arrangement of holes is also called a «pattern». This pattern depends of the source applications, a large flux will require a large number of holes compared to an application where only a very small flux is required. The atoms have generally a very low recombination coefficient, so even those undergoing several wall collisions will ultimately contribute to the atom beam flux. The electron sheet, covering the inside cavity wall, the hole sizes and shapes are designed to minimize ions and electrons released from the cavity (Current lower then 10nA/cm2). The gas breakdown will occur above a certain pressure in the cavity. This pressure depends on the gas ionization potential. In consequence and for a given cavity pattern (number of holes times the diameter of holes or cavity conductance) the flow rate of molecular gas will vary from gas to gas. SPECIFICATIONS Characteristics S40 RF X 450 S63 RF X 600 S63 RF S100 RF X Plasma Generated by Radio Frequency Wave Cavity PBN (N2 / H2) or Synthetic Quartz (O2 / H2) Type One piece Open with removable diffuser RF tuning unit Manual or Automatic Mounting flange CF 40 CF 63 CF 63 CF 100 Water / gas / electrical Max - RF Power 450 W 600 W 600 W 600 W RF Generator RF Input connector Gas Inlet Manual Leak valve Water Connection RF Coil Cooling RF Tuning unit Cooling Water Security Switch Mhz / 600 W Female N Type DN 16 CF / VCR 1/4" F Included Swagelok Ø6 mm DP > 4 bar / 0.3 l/min Air Yes Pneumatic Connection* N.A. Ø4 mm tube fitting N.A. N.A. Options Gas Panel + MFC + Controller Gas Purifier Panel Plasma Optical Monitor Integrated Shutter Nipple Shutter Refer to gas handling chapter O2 / H2 / N2 refer to gas handling chapter Plasma light detector chapter N.A. N.A. : Non applicable

3 RESULTS Working conditions of the RF50/63 on a C21 machine. Photo luminescence of GaN on Al2O3 obtained with the RF-N-600 on a Compact 21 Riber system. The growth is performed at 780 C with a Nitrogen flow rate of 0.65 sccm of nitrogen achieving a deposition rate of 0.4µm/h. PL Line width of 4meV is obtained. Set of RF power and nitrogen flow parameters for a fixed value of optical sensor output U Control the deposition rate with OED The data presented were achieved by Dr. Z.R Zytkiewicz and his coworkers. Institute of Physics, Polish Academy of Amazing GaN growth rate achieved, up to 2.5 µm/h with superb crystalline quality using Riber RFN-50/63. With the courtesy of B. McSkimming and J. Speck, UCSB (USA). sciences, Poland.

4 CONNECTION Isolation valve Gas Panel Mass flow Purifier panel 5 Purifier GUN MATCHING BOX GAS LINE ACCESSORIES automatic matching box n Automatically match impedance of plasma source with a 600 watts RF generator Equipped with 2 modules systems : n Compact air-cooled PI-type matching network (Connected directly the RIBER RF source) n External controller unit (PLC fitted on a rugged interconnection box) n The AIM can be adapted on any RIBER RF plasma source Matching box n Controller unit & AIM network are connected with single cable AIM n An embedded RS232-C interface can be extended by a RS422/485 expansion unit n Paddle is provided to give a convenience control OED

5 source selection guide Systems source model S40 RF-X-450 S63 RF-X-600 S63 RFX 50/63 S100 RFX 50/100 MBE 32 Compact 12 Compact 21 RIBER EPINEAT MBE 412 MBE 49 MBE 6000 MBE 7000 GEN II MOD GEN II VEECO / VARIAN GEN 930 GEN 200 GEN 2000 V80 VG V90 V100 V150 OTHER SYSTEMS Riber sources are also available for use on systems from Eiko, Anelva, Ulvac, SVTA and DCA, as well as custom chambers. Contact Riber for details. RECOMMENDED CONTACT RIBER FOR MORE DETAILS INAPPROPRIATE For the ordering information please contact Riber

6 Technological leadership Riber is the world leading supplier of MBE processing equipment and related services. In total, 850 of our MBE systems have been installed with at least one system in each of the 35 countries with which MBE is involved. This represents 75% of the global market. Capitalizing on more than 30 years of experience, the company s core philosophy is to design systems in close association with customers. Riber has invented and designed major features which are now found in all MBE systems. Riber plays a key role in the development of MBE technology, providing customers with solutions from equipment to epitaxial growth. worldwide presence Headquarters and subsidiaries Representatives For more information: Tel: +33 (0) info@riber.com Internet: S Technical specifications reserved RIBER - 31, rue Casimir Périer, B.P 70083, Bezons, France Tel: +33 (0) Fax: +33 (0) info@riber.com Internet: