Yutaka Inouchi

• Nissin Ion Equipment Co., Ltd., Japan

Activation and carrier generation are reported in the case of phosphorus implantation with a dose of 2.0 × 10¹⁵ cm⁻² at 70 keV to crystalline silicon substrates under heating ranging from 200 to 500 °C. The analysis of the optical reflectivity spectra of implanted surfaces revealed that the effective amorphized thickness was low of 2.9 nm in the ca...

Ion doping tools which have ability to process large size glass substrate with high productivity are briefly described. Such tools might develop new fields that utilize ion implantation technology. So far we tried several applications. In this study, three applications for which large area treatment will be essential to commercial production are re...

A plasma flood gun (PFG) has been developed for Nissin implanter "iG5 [1]" and "iG6" for Gen. 5.5 and 6.0 flat panel display (FPD) process. The PFG with a filament cathode can supply high electron flux in order to neutralize the surface charge of glass substrate irradiated by the high current ion beam [2]. We investigated the charge-up of the targe...

For the manufacturing process of display for mobile devices using Low Temperature Poly-crystalline Silicon Thin Film Transistor (LTPS-TFT), ion doping processes have been required. Nissin developed ion doping systems which were referred as iG series and they have already been used in production lines of many panel makers. In these systems, the basi...

Ion beam instabilities on a wide ribbon beam which cross-section is 150 cm × 10 cm are discussed. At low energy conditions, we detected two kinds of instabilities on the ion beam extracted from BF3 plasmas. One kind of the instabilities is that onset of the instability is dependent on the extraction current from the ion source. This instability occ...

We developed a multi-cusp ion source for Nissin ion doping system iG5 which is used in low temperature poly-crystalline silicon processes for flat panel display (FPD) manufacturing. In this ion source, BF3 or PH3 diluted H2 plasmas are produced and large area ribbon ion beams are extracted. In general, ion ratio of B(+) in BF3 plasma is much smalle...

Ion sources for ion implantation are introduced. The technique is applied not only to large scale integration (LSI) devices but also to flat panel display. For LSI fabrication, ion source scheduled maintenance cycle is most important. For CMOS image sensor devices, metal contamination at implanted wafer is most important. On the other hand, to fabr...

We report a simple method with a commercial microwave oven for activation of 22 Ωcm p-type silicon implanted with phosphorus atoms a dose of 1.0×1015 cm-2 at 1000 W for 9 min. Microwave transmittance measurement revealed a sheet resistance of 209 Ω/sq and an activation ratio of 60 %. The microwave heating achieved recrystallization of the amorphize...

We have developed a new implantation tool for the generation 5.5 glass. 150 cm high ion beams, which are bigger than the glass height, are extracted from the ion source. After being bent by the mass separation magnet, the beams reach the glass which is standing upright. The new tool exhibits high throughput in high dose applications because of high...

A multi-cusp ion source was designed for Nissin ion doping system "iG5" developed for GEN5.5 processes. It has many points of similarity to iG4 ion source. The extraction area and the internal volume of the plasma chamber are scaled up. And the method to obtain high current B+ beams is same as iG4 ion source. On the other hand, iG5 ion source has a...

Buried void layer formation in silicon substrates was achieved by hydrogen ion implantation fol-lowed by 940-nm infrared laser rapid heating. P-type silicon substrates coated with 100-nm-thick thermally grown SiO2 layers were implanted with hydrogen atoms at 5x10 15 and 3x10 16 cm -2 at 60 keV. Structural investigation with analysis of optical refl...

We report precise analysis of photo‐induced carrier recombination properties in the case of hydrogen ion implantation to silicon substrates. Hydrogen ion implantation markedly decreased the effective minority carrier lifetime (τ eff ) from 631 to 3.9 μs and increased the surface recombination velocity (S) from 50 to 12000 cm/s. 1.3×10 6 Pa...

An accurate dose distribution control system was developed for a Nissin iG4 ion implanter, which is utilized for low temperature polycrystalline silicon thin film transistors (LTPS‐TFT), to improve dose uniformity under a photoresist outgas environment. The system consisted of a scan speed controller for glass substrates and monitors of ion beam...

A Nissin iG4 ion doping system (termed iG4) utilizes broad beam technology to implant GEN 4 sheets of glass for LCD production. The mechanical scanned end‐station with robotic handling for GEN 4 glass substrates was redesigned, and a new end‐station was built to handle rectangular silicon tiles (23×18 cm ). A three sub‐system modular risk redu...

In a multi-cusp ion source, magnetic boundaries, together with the difference between plasma potential and plasma chamber potential, functioned as a mass filter which filters out heavier ions in multi-component plasmas. This method was applied to mixed inert gas plasmas and hydrogen plasmas and found to be very effective for general purposes which...

A multi-cusp ion source with large area extraction area has a capacity to extract high current ion beams. However it is difficult to obtain high current boron ion beams from boron trifluoride plasma as input power density is low and BF2+ is a main ion species. It was found that fluoride ion currents were selectively decreased by applying positive p...

A mass analyzing ion implantation system (called Ion Doping iG4) was developed for FPD manufacturing. One of most important concept of iG4 is to transport a sheet ion beam maintaining its current density profile from the ion source to the target, which leads good mass resolution and simple control of the beam profile. The system has a bucket type...

A compact DC-plasma flood gun (DC-PFG) producing (50 mA) electron flux was developed for neutralization of a large size ion beam in doping process of flat panel displays (FPD). To produce the high current electron flux, this PFG contains a multi-cusp type arc chamber with a tungsten filament cathode, single hole to extract the electron and a drift...

Large area ion sources have been used in ion doping systems in the field of LCD production. In these ion sources good uniformity and wide dynamic range in beam current are both required to achieve the good dose uniformity in wide dose range. A new ion source which uses dc arc discharge with three filaments, each of which is controlled individually,...

The Nissin ion doping system ID6700 for TFT LCD fabrication uses a large area ion source generating a uniform line beam which irradiates a large glass substrate. A uniform ion beam can be obtained across a large substrate over 600 mm, which is automatically tuned by individually adjusting the heating currents of the three filaments based on the bea...

ECR ion sources in general have good properties such as long lifetime and high output of multiply charged ions although the dynamic range of beam current is quite narrow. An ECR ion source which can generate a wide range of beam current is developed for a medium current implanter. The source magnetic fields are produced by two solenoids each of whi...

A high energy beam line system which comprises a radio frequency quadrupole (rfq) and 3-gap radio frequency (rf) accelerators is developed for high energy ion implanter. The rfq bunches and accelerates an ion beam to a fixed energy and the following 3-gap rf accelerators further accelerate or decelerate the ion beam to give continuous energy variat...

For development of a mass separated high current (>100 mA) metal (Cr + ,Si + ,etc.) ion implantation system, beam transport characteristics through a mass separator were investigated. When a 121 mA Cr ion beam was extracted at the extraction voltage of 37 kV, Cr + beam of 79 mA passed through the 90° sector magnet with a bending radius of 50 cm, a...

R & D project of high current metal ion beam technology is being carried out for use in material surface modification and new material formation by means of ion implantation. Present results of the R & D are as follows. (1) A multicusp high temperature metal ion source with an operation temperature of 2000 degrees K was attained using heat reflecto...

The continuous control of Cr ion beams from low energy to high energy in a single ion beam system was attempted. For this wide energy range control, a deceleration tube was connected to an acceleration tube. The Cr ion beams extracted from a metal ion source were mass separated and accelerated or decelerated in the acceleration or the deceleration...

Improvements have been made in a metal ion source, which made it possible to produce high density metal vapor plasma for extracting high current metal ion beams. Experiments of chromium ion beam extraction were performed. The ion beam current reached 250 mA at the extraction voltage of 36 kV. Furthermore, stable operation was achieved at the extrac...

A metal ion source has been developed for extracting high current ion beams of high melting point metals. In the discharge chamber, metal vapor was confined in high‐temperature shields, and the pure metal plasma was produced by the arc discharge. In order to prevent the vapor deposits, the extraction electrodes were also required to be high tempera...

Ion charge state and impurities extracted from a multicusp ion source have been studied with the use of a magnetic momentum mass analyzer. Impurities contained in high current metal ion beams are crucible materials (such as Al2O3, BN, Y2O3, C) and high melting point materials (such as Mo, Ta, W). To reduce these impurities, the dependence of the im...

A high current metal ion accelerating system, which consists of a metal vapor plasma ion source with a multicusp magnetic field and a single gap acceleration column, has been developed. The following results were obtained experimentally: (1) a 110 mA aluminum ion beam and a 95 mA chromium ion beam were extracted from the ion source, (2) the impurit...

Improvements have been made in a multicusp ion source, which made it possible to produce metal–vapor plasma and extract a high‐current metal ion beam. In the discharge chamber, double radiation shields were set and the inner shields were heated to 1860 K. Therefore, it became possible to maintain enough metal–vapor density to produce plasma without...

A magnetic multipole ion source with some modifications to sustain high density metal vapour plasma has been developed and investigated. The following results are experimentally obtained for aluminium plasma: (1) the inside of the ion source is heated up to about 1500 K to sustain the metal vapour density necessary for a discharge; (2) the high pur...