초록 ▼

Process for forming a fragile layer inside of a single crystalline substrate near one of the substrate surfaces. The fragile layer contains hydrogen mostly in form of hydrogen platelets oriented in parallel to each other and to neighboring crystal surface. The fragile layer is preferably grown withi

Process for forming a fragile layer inside of a single crystalline substrate near one of the substrate surfaces. The fragile layer contains hydrogen mostly in form of hydrogen platelets oriented in parallel to each other and to neighboring crystal surface. The fragile layer is preferably grown within a single crystalline silicon wafer to facilitate the detachment of an overlaying thin layer of single crystalline silicon from the initial wafer. The hydrogen layer is grown on a seed layer. The seed layer is preferably formed by ion implantation of inert gases at doses in 1015 cm-2 range. The hydrogen layer is grown by plasma hydrogenation of the substrate. The hydrogenation process begins at substrate temperature not exceeding 250째 C., and than continues at higher temperature not exceeding 400째 C. The method can be used to fabricate silicon-on-insulator (SOI) wafers wherein a thin layer of single crystalline silicon is detached from a silicon substrate along the fragile layer and attached to a substrate with an insulator on top of that substrate.

대표청구항 ▼

I claim: 1. A method wherein a fragile layer is formed within a first substrate, wherein the improvement comprises forming said fragile layer via at least two processing operations, including: (a) a first processing operation, wherein said first processing operation is conducted at a first temperat

I claim: 1. A method wherein a fragile layer is formed within a first substrate, wherein the improvement comprises forming said fragile layer via at least two processing operations, including: (a) a first processing operation, wherein said first processing operation is conducted at a first temperature that falls within a first range of temperatures; and (b) a second processing operation, wherein said second processing operation is conducted at a second temperature that falls within a second range of temperatures, wherein said first range of temperatures is different than said second range of temperatures. 2. The method of claim 1 wherein said first processing operation comprises nucleating platelets. 3. The method of claim 2 wherein said first processing operation further comprises: (i) forming hydrogen plasma; and (ii) exposing said first substrate to said hydrogen plasma. 4. The method of claim 3 wherein said first range of temperatures includes temperatures that do not exceed 250째 C. 5. The method of claim 3 wherein a maximum temperature of said first range of temperatures is less than a maximum temperature of said second range of temperatures. 6. The method of claim 1 wherein said first processing operation further comprises: (i) implanting impurities in said first substrate, wherein said impurities do not chemically interact with said first substrate; and (ii) gasifying said impurities, thereby forming bubbles within said substrate. 7. The method of claim 6 wherein sub-operation (ii) further comprises forming plastic deformations around said bubbles. 8. The method of claim 6 wherein sub-operation (i) occurs at about room temperature and sub-operation (ii) occurs at said first temperature, and wherein said first range of temperatures includes temperatures that are at least about 300째 C. and no more than about 700째 C. 9. The method of claim 6 wherein said first processing operation occurs at said first temperature, and wherein said first range of temperatures includes temperatures that are at least about 300째 C. and no more than about 700째 C. 10. The method of claim 6 wherein said impurities are selected from the group consisting of hydrogen, helium, neon, argon, krypton, and xenon. 11. The method of claim 6 wherein a maximum temperature of said first range of temperatures is greater than a maximum temperature of said second range of temperatures. 12. The method of claim 1 wherein said second processing operation comprises growing platelets. 13. The method of claim 12 wherein said second range of temperatures includes temperatures that are at least 250째 C. and no more than 400째 C. 14. The method of claim 1 further comprising forming a vacancy cluster-enriched layer within said first substrate and proximal to a first surface of said first substrate, wherein said fragile layer is formed at said vacancy cluster-enriched layer by performing said first processing operation and said second processing operation. 15. The method of claim 14 wherein said vacancy cluster-enriched layer is formed by implanting ions within said first substrate. 16. The method of claim 15 wherein said ion are selected from the group consisting of silicon and germanium. 17. The method of claim 14 wherein said method is for forming a SOI wafer, wherein said method further comprises: providing a second substrate, wherein said second substrate comprises a dielectric layer, and wherein said dielectric layer is disposed on a major surface of said substrate; forming a wafer assembly by temporarily coupling said second substrate, at said dielectric layer, to said first surface of said first substrate; and cleaving said wafer assembly at said fragile layer, wherein, as a result of said cleaving, a portion of said first wafer remains attached to and overlies said dielectric layer, thereby forming said SOI wafer. 18. A method comprising: forming a vacancy cluster-enriched layer within a substrate; forming nuclei of hydrogen platelets at said vacancy cluster-enriched layer, wherein said nuclei are formed at a first temperature within a first range of temperatures; and growing said hydrogen platelets from said nuclei, wherein growing is performed at a second temperature within a second range of temperatures, wherein said second range of temperatures has a minimum temperature of about 250째 C. and a maximum temperature of about 400째 C., wherein said first range of temperatures has a different minimum temperature and a different maximum temperature than said second range of temperatures. 19. A method comprising forming a fragile layer in a substrate, wherein: (a) said fragile layer is formed via a first sub-operation and a second sub-operation; (b) said first sub-operation is carried out at a first temperature that falls within a first range of temperatures; (c) said second sub-operation is carried out at a second temperature that falls with a second range of temperatures, wherein said second range of temperatures is between 250째 C. and about 400째 C.; (d) said first range of temperatures is different than said second range of temperatures; and (e) said second sub-operation comprises plasma hydrogenation.