Wire saw slicing ultra thin silicon wafers

Información del proyecto

Identificador del acuerdo de subvención: JOUR0095

Proyecto cerrado

Fecha de inicio 1 Noviembre 1990

Fecha de finalización 31 Octubre 1992

Financiado con arreglo a

• Specific research and technological development programme (EEC) in the field of energy - non-nuclear energies and rational use of energy - (JOULE), 1989-1992

Coste total

Sin datos

Aportación de la UE

Sin datos

Coordinado por

Photowatt International SA
France

Objetivo

To reduce the cost of crystalline silicon wafers the project will study the operating conditions of a new prototype two table wire saw required to :

- slice multicrystalline silicon bricks with reduced silicon usage (wafer thickness + kerfloss)
-slice such bricks at higher speeds.
To reduce the cost of crystalline silicon wafers a study was made of the operating conditions of a new prototype 2-table wire saw. The saw is required to slice multicrystalline silicon bricks with reduced silicon usage (wafer thickness plus kerfloss) at high speeds.

The previous (1990) cutting speeds of 240 um min{1} for reached for 10 cm walls and 260 um min{1} 15 cm cells increased in 1991 to 330 um min{1} and 370 um min{1} respectively. The goal of 520 um min{1} could be attained in 1992. A reduction in wafer thickness from 170 to 150 um was achieved.
The work program will cover :

1) The characterisation of the wire and its wear in the course of the sawing operation.

2) The feasibility of surface treatment and composition changes of the steel wire to reduce its wear and eventually resulting in a more uniform wear.

3) The feasibility of using wire materials other than steel.

4) The testing of wires having diameters lower than the 175 microns presently used.

5) The optimisation of the cutting parameters (wire tension, wire and table speeds, feed and composition of the abrasive slurry) to :

a) maintain high wafering yields at wire pitches lowered from the present 400 microns down to 300 microns.
b) maintain high yields at lowered wire pitches when pushing the cutting speed (table speed) from 260 microns/minute to 520 microns per minute and while cutting simultaneously two ingots of 15 x 15 cm2 (one on each table) or four ingots of 10 x 10 cm2 (two each table).

6) Analysis of potential capacity improvements by:

a) alternate abrasive mixes usable under high heat fluxes
b) inducing controlled high frequency vibrations into the cutting head during operation
c) very high wire speeds

7) Analysis of effects on cutting capacity of small variations of silicon material hardness.

8) Final economical assessment of all the technical improvements considered.

Experimental phases of the program will be carried out in parallel by Photowatt and ENE by cutting respectively 10 x 10 cm2 and 15 x 15 cm2 wafers. The prototype machine is built by HCT for ENE and will remain at the HCT plant for a number of trials associated with paragraphs 4, 5, 6 and 7 of the program above.

Ámbito científico (EuroSciVoc)

• ciencias naturales › ciencias químicas › química inorgánica › metaloides

Programa(s)

• FP2-JOULE 1 - Specific research and technological development programme (EEC) in the field of energy - non-nuclear energies and rational use of energy - (JOULE), 1989-1992

Tema(s)

Datos no disponibles

Convocatoria de propuestas

Datos no disponibles

Régimen de financiación

CSC - Cost-sharing contracts

Coordinador

Photowatt International SA

• Aportación de la UE: Sin datos
• Dirección: 33 rue Saint-Honoré Zone Industrielle Champ Fleuri ; 38300 Bourgoin-Jallieu ; Francia
• Coste total: Sin datos

Participantes (2)

E.N.E. SA - ENERGIES NOUVELLES ET ENVIRONNEMENT

Bélgica

• Aportación de la UE: Sin datos
• Dirección: Avenue Van Der Meerschen 188 ; BRUXELLES
• Coste total: Sin datos

HCT Shaping Systems SA

Suiza

• Aportación de la UE: Sin datos
• Dirección: 42,Route de Genève ; 1033 Cheseaux
• Coste total: Sin datos