Mitsuaki Kabasawa

Introduction of the SHX‐III System, a Single‐Wafer High‐Current Ion Implanter

The SHX‐III system, categorized as a single‐wafer high‐current ion implanter, has been developed by SEN Corporation in order to meet all the requirements for high dose and relatively high mid‐dose applications, including high‐tilted multi‐step implantation. Recently the three major advanced device types, namely logic devices, memory and imagers, started to require high‐current ion implanters in diverse ways. The SHX‐III is designed to fulfill such a variety of requirements in one system. The SHX‐III has the same end station as the MC3‐II/WR, SEN’s latest medium current implanter, which has a mechanical throughput of 450 WPH. This capability and precise dose control system of the SHX‐III causes dramatic productivity enhancement for application of mid‐high dose, ranged between 5E13 to 2E14 atoms/cm2, usually performed by medium current ion implanters. In this paper the concept and performance of the SHX‐III will be described, concerning influence of device characteristics. A concept and performance data of ...

Introduction of the S-UHE, a single-wafer ultra-high energy ion implanter

In order to address the process requirements of leading-edge image sensors, a new single-wafer ultra-high energy ion implanter, the S-UHE, has been developed. This product incorporates two exceptional subassemblies. One is the eighteen-stage RF linear accelerator from the UHE, a multi-wafer ultra-high energy implanter, offering maximum beam energy of 2MeV per charge. The other is the field proven end station used by the MC3-II/GP, a single-wafer medium current implanter, which can provide throughput of over 450 wafers/hour. The S-UHE has a unique beam line concept where beam energy analyzing magnets bend the accelerated beam 180°. This system minimizes tool footprint, providing additional space for maintenance. Other key elements of the beam line include an electrostatic scanner, parallelizing lens and energy filter. The electrostatic scanner provides higher scan speed than mechanical systems - significantly improving dose uniformity compared to a batch high energy implanter. Additionally, the S-UHE ensures accurate implant angles and ultra-low level of metal contamination, both of which are very important parameters for advanced image sensors.

Precise beam angle control in the S-UHE, SEN's single-wafer ultra-high energy ion implanter

In order to fabricate highly sensitive image sensors (IS), ultra-high energetic ion beams such as 5MeV of boron are required. In order to address the requirement as well as more aggressive requirements of leading-edge IS, SEN has developed the S-UHE, an ultra-high energy single-wafer ion implanter. One of the most important features in the S-UHE is a precise beam angle control system to obtain stable implant depth of ion species against angle-sensitive channeling effects. It is very important for the precise control both to design a sophisticated beam line and to measure beam angles accurately. In this report, measuring techniques of the beam angle and the results are presented.

Profile and Angle Measurement System of SHX

To cope with the manufacturing processes for shrunk semiconductor devices, a precise implant angle control is required for the latest generation of ion implanters. Various ideas are incorporated into the SHX, a single wafer type high current ion implanter developed by SEN Corporation, to meet the requirements not only with a newly designed beam line but also with an accurate angle monitoring system.In the SHX, an ion beam is transported to the electrostatic beam scanning system after a mass analysis. The scanned beam passes through Parallel Lens to be arranged in the parallel direction. Next, the beam is bent vertically by the energy filter and reaches the wafer platen, finally. The beam profile measurement system, Beam Profiler, is positioned on the same plane as the wafer.The Beam Profiler can measure horizontal uniformity of the scanned beam current. Using the Divergence Mask, information about the horizontal beam parallelism at the wafer position also can be acquired. In addition, 2‐dimensional profil...

Sheet Resistance Dependence on Ion Angle Deviation

This paper will examine the influence of ion angle deviation (IAD) on sheet resistance. The IAD is derived from the beam intensity profile measured in the MC3-II/GP medium current implanter. IAD is controlled independently in the horizontal and vertical directions by tuning voltages in the Qlens. It was found that the sheet resistance (Rs) regularly increases with an increase of IAD at a tilt of 0° where strong channeling occurs, while the Rs is constant for various IADs at a tilt of 7°. These results suggest that the Rs at 0° is suitable for use as an IAD monitoring method and that the IAD can be flexibly controlled in the MC3-II/GP.

Symmetric beam line technique for a single-wafer ultra-high energy ion implanter

In order to fabricate highly sensitive image sensors, ultra-high energy ion beams, such as 5 MeV of boron, are required. SEN has developed the S-UHE, a single-wafer ultra-high energy ion implanter, to obtain such ultra-high energy beams. The S-UHE has adopted an electrostatic and symmetric, parallelizing lens system, the concept of which is already used in the MC3-II, a medium-current ion implanter, and the SHX, a single-wafer high-current implanter. This system provides very good uniformity, even when a large amount of outgassing from photoresist materials is generated. Since the ion beam energy is so high at the lens system, a compound electrostatic parallelizing lens system is introduced. Beam angles have been controlled within 0.05° for any recipe in experiments with the electrostatic parallelizing lens system. Another beam line element specifically adopted in the S-UHE is an electric quadrupole lens installed between the two dipole magnets, in order to suppress beam current loss. This electric lens can easily form achromatic ion beam transportation without any significant deformation of the magnetic field.

SAion - SEN's unique solution for 450mm ion implant

The SAion-450 is a leading-edge ion implanter developed for the upcoming 450mm wafer generation. The SAion-450 has extremely wide process coverage and productivity throughout both the medium current (MC) and high current (HC) process ranges. Although the area of a 450mm wafer is 2.25 times larger than that of a 300mm wafer, the SAion-450 can process typical MC recipes with higher productivity than the current 300mm MC implanter, the MC3-II/GP. Additionally, low energy (LE) productivity can be significantly enhanced with the addition of the LE beam line option. This can be easily installed (or removed) in a production fab. The SAion product line also includes a 300mm model. The SAion-300 is equipped with the same beamline as the SAion-450 in order to deliver the same process characteristics in 300mm fabs as in 450mm wafer lines. Thus, the SAion series can serve as a bridge tool to assure smooth wafer size transition from 300mm to 450mm.

Intentional Two-Dimensional Non-Uniform Dose Implant with High Dynamic Dose Range

Two-dimensional (2D) dose control is becoming well accepted for semiconductor device fabrication. At the same time, two specialized versions are arising; (1) High accuracy intentional non-uniform dose implant with relatively moderate dynamic dose range and (2) High dynamic dose range intentional non-uniform implant with relatively moderate dose accuracy. Sumitomo Heavy Industries Ion Technology (SMIT) has developed two-dimensional intentional non-uniform doseimplant methods for both demands. A method to carry out a high-accuracy intentional 2D non-uniform implant (MIND 2.0) will be presented at this conference. In this paper, our method to carry out a high-dynamic-range 2D non-uniform dose implant will be reported. A test implant was planned and carried out for an intentional doughnut-shape dose pattern by using the MC3-II/GP ion implanter. While the implant dose in the outmost region is neglected, we could obtain in the inner region about ten times smaller dose than in middle region in a wafer.

High-Accuracy Two-Dimensional Intentional Non-Uniform Dose Implant: MIND 2.0

Two-dimensional (2D) dose control is becoming well accepted for semiconductor device fabrication. At the same time, two specialized versions are arising; (1) High accuracy intentional non-uniform dose implant with relatively moderate dynamic dose range and (2) High dynamic dose range intentional non-uniform implant with relatively moderate dose accuracy. Sumitomo Heavy Industries Ion Technology (SMIT) has developed two-dimensional intentional non-uniform dose-implant methods for both demands. A method to carry out a highdynamic- range 2D non-uniform dose implant will be presented at this conference. In this paper, the method to carry out high-accuracy intentional 2D non-uniform implants (MIND 2.0) will be reported. The MIND 2.0 system has been installed on SMITs hybrid-scan single-wafer ion implanters. In order to obtain intentional non-uniform dosage, beam scanning patterns must be modified. For a high-accuracy intentional 2D non-uniform dose implant, an iterative method which includes actual dose-pattern checks has been implemented in MIND 2.0. In this way, appropriate beam scanning patterns for intended twodimensional non-uniform dose patterns are always obtained, no matter what a beam size is.

A Beam Quality Control Method in SAion Ion Implanter

The SAion is a leading-edge ion implanter developed for the upcoming generation. The SAion has extremely wide process coverage and high productivity throughout both the medium current (MC) and high current (HC) process ranges. In this paper, beam quality control method introduced for the SAion will be discussed. In order to carry out beam quality control, methods both to measure beam quality very precisely and to control beam quality very precisely must be satisfied simultaneously. These two technical elements have been developed and adopted in the SAion. A movable beam profiler has a beamangle measurement function in very high accuracy. A beam angle is measured very precisely at the wafer position. Based on the measurement, beam divergence control with extremely wide beam current coverage also can be carried out.