Elimination of Non-stick on Leads Defect through Re-designed WCTP

This paper presents the reformation and fabrication resolved on the wire clamp and top plate (WCTP) design to eliminate the presence of lead finger bouncing resulting to high rejection of non-stick on leads (NSOL). Problem experienced was that the hollow or half-etched portion of the leadframe at the top and bottom units caused its bouncing effect. With the aim to improve localized massive NSOL defect, WCTP has been modified to provide positive bias to support its hollow part or the half-etched part of the leadframe at the top and bottom of the units. The re-designed WCTP was fabricated, extending its clamping with enhanced vacuum on top and bottom rows. The implementation of the improved WCTP design reduced the defect with 88 % improvement with the defect reduction during the lot runs.

Assembly Wirebond Process Solution for Mitigating Leadframe Bouncing on Multi-Die QFN Device

Modification and improvement of an existing tooling design in semiconductor packaging industry has been a usual practice, to enhance the current setup and to provide a solution to a specific assembly problem. This paper discusses the solution in eliminating the smashed ball defect occurrence observed after wirebond process. Smashed ball is usually encountered if the unit is unstable and creates a bouncing effect during wirebond process. It is therefore important to mitigate this micro-bouncing effect by analyzing the package design and the window clamp and top plate (WCTP). The objective is to increase the stability of the unit during wirebonding, especially for quad-flat no-leads (QFN) package with no tape. To achieve this, the solution is to alter the vacuum hole design of the top plate from single hole per unit to multiple holes of varied sizes per unit. Ultimately, after changing the design of the top plate, the micro-bouncing encountered during wirebond process was significantly reduced. This in turn created a consistent ball formation in all bonded wires. The comparative data presented in this paper confirmed the effectivity of the redesigned WCTP. For future works and studies, the improvement and learnings could be used on devices with comparable configuration.

Off-centered Ball Resolution Through Multi-hole Process Plate Implementation at Wirebond Process

With the continuous trend of new technologies in semiconductor manufacturing assembly, challenges and issues are unavoidable. This paper presents the modification and improvement done on the process plate design to eliminate the bouncing effect of the silicon die that leads to off-centered ball (OCB) reject during the formation of wire on a quad flat no-leads (QFN) device. The panel type single-row process plate cannot totally vacuum the warped leadframe and this is resulting to off-centered ball. Through changing the panel type single-row process plate to panel type multi-hole process will have a strong vacuum sucked underneath the leadframe and eliminates the occurrence of off-centered ball. Future works could use the improved process plate design for devices of similar configuration.

Multi-Hole Process Plate Modification for Chip on Lead Device at Die Attach Process

The paper focused on the improvement done in chip on lead (COL) leadframe package assembly manufacturing to address the leadframe bouncing effect during die attach process. A new and enhanced process plate is designed with multi-hole configuration to provide a strong vacuum underneath the leadframe and to maintain the planarity during dispensing and die bonding of silicon dies onto the leadframe. With the new multi-hole process plate, leadframe bouncing was successfully eliminated during die attach process. For future works, the multi-hole process plate could be used on devices with similar configuration.

Elimination of Smashed Ball Defect through Process and Design Improvement

This paper presents the modification and improvement done on the wire clamp and top plate (WCTP) design to eliminate the bouncing effect of the silicon die that leads to smashed ball reject during the formation of wire. The protrusion of the unit on the vacuum hole produced movement and slight vibration that affects the consistency of wirebonding. Through changing the standard vacuum hole to micro-holes provides underneath support to the unit and eliminates the overhanging or protrusion during the formation of wire. The implementation of the micro-hole design reduced the defect parts per million (dppm) occurrence to zero.

OPTIMALISASI TEKANAN SHOCK ABSORBER DAN TEKANAN PEGAS COIL TERHADAP GETARAN MOBIL

Safety and comfort are the valuable factor for the driver. One of the safety factor refers to the steering accuracy. Steering wheel hardness must be soft when turning but remain stable in straight track. The comfort factor refers to the bouncing effect when the car passing in rough track. Those two factors is depend on the shock absorber components. This study aims to know the optimum gas pressure and spring pressure to obtain the maximum vibration reduction. This study use the experimental methods use the 6 bar, 8 bar, and 10 bar of absorber pressure. The spring pressure used in this study is 20 , 25 dan 30 (Kg/cm2). The data obtained were analyzed with MINITAB software. From the results of research on Optimizing Shock Absorber Pressure and Coil Spring Pressure Against Car Vibrations can be concluded as follows: 1. There is an influence of absorber pressure and spring pressure on the suspension on the amount of vehicle vibration. The optimum absorber pressure is 10 (bar). 2. The optimum coil spring pressure at 24 (kg / cm2).